- connectionsJunction connections
C++ Type:std::vector<BoundaryName>
Unit:(no unit assumed)
Controllable:No
Description:Junction connections
JunctionOneToOne1Phase
This is a flow junction that connects 2 FlowChannel1Phase components and assumes that there is no loss of momentum, even if the connected flow channels are not parallel.
Using this junction between 2 flow channels should be numerically equivalent to having the 2 connected flow channels merged into 1 large flow channel. This junction is useful for cases where a separation in a flow channel is required. One particular example is when a heat structure is connected to a section of an otherwise single flow channel.
Formulation
This junction is treated just like any interface between two elements in the mesh.
Usage
The parameter "connections" specifies ends of flow channel components to connect.
Input Parameters
- control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Unit:(no unit assumed)
Controllable:No
Description:Adds user-defined labels for accessing object parameters via control logic.
- enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
Description:Set the enabled status of the MooseObject.
Advanced Parameters
Input Files
- (modules/thermal_hydraulics/tutorials/single_phase_flow/04_loop.i)
- (modules/thermal_hydraulics/test/tests/problems/freefall/freefall.i)
- (modules/thermal_hydraulics/test/tests/problems/brayton_cycle/closed_brayton_cycle.i)
- (modules/thermal_hydraulics/tutorials/single_phase_flow/06_custom_closures.i)
- (modules/thermal_hydraulics/test/tests/problems/brayton_cycle/open_brayton_cycle.i)
- (modules/thermal_hydraulics/test/tests/problems/area_constriction/area_constriction_junction.i)
- (modules/thermal_hydraulics/test/tests/components/junction_one_to_one_1phase/constriction_1phase.i)
- (modules/thermal_hydraulics/test/tests/base/simulation/loop_identification.i)
- (modules/thermal_hydraulics/test/tests/problems/natural_circulation/junction_one_to_one.i)
- (modules/thermal_hydraulics/test/tests/problems/brayton_cycle/recuperated_brayton_cycle.i)
- (modules/thermal_hydraulics/tutorials/single_phase_flow/05_secondary_side.i)
- (modules/thermal_hydraulics/test/tests/problems/pressure_drop/pressure_drop_with_junction.i)
- (modules/thermal_hydraulics/test/tests/components/junction_one_to_one_1phase/junction_one_to_one_1phase.i)
- (modules/thermal_hydraulics/tutorials/single_phase_flow/03_upper_loop.i)
connections
C++ Type:std::vector<BoundaryName>
Unit:(no unit assumed)
Controllable:No
Description:Junction connections
(modules/thermal_hydraulics/tutorials/single_phase_flow/04_loop.i)
T_in = 300. # K
m_dot_in = 1e-2 # kg/s
press = 10e5 # Pa
# core parameters
core_length = 1. # m
core_n_elems = 25
core_dia = '${units 2. cm -> m}'
core_pitch = '${units 8.7 cm -> m}'
# pipe parameters
pipe_dia = '${units 10. cm -> m}'
A_pipe = '${fparse 0.25 * pi * pipe_dia^2}'
A_core = '${fparse core_pitch^2 - 0.25 *pi * core_dia^2}'
P_wet_core = '${fparse 4*core_pitch + pi * core_dia}'
Dh_core = '${fparse 4 * A_core / P_wet_core}'
tot_power = 2000 # W
[GlobalParams]
initial_p = ${press}
initial_vel = 0.0001
initial_T = ${T_in}
initial_vel_x = 0
initial_vel_y = 0
initial_vel_z = 0
gravity_vector = '0 0 0'
rdg_slope_reconstruction = minmod
scaling_factor_1phase = '1 1e-2 1e-4'
scaling_factor_rhoV = 1
scaling_factor_rhouV = 1e-2
scaling_factor_rhovV = 1e-2
scaling_factor_rhowV = 1e-2
scaling_factor_rhoEV = 1e-4
closures = simple_closures
fp = he
[]
[FluidProperties]
[he]
type = IdealGasFluidProperties
molar_mass = 4e-3
gamma = 1.67
k = 0.2556
mu = 3.22639e-5
[]
[]
[Closures]
[simple_closures]
type = Closures1PhaseTHM
[]
[]
[SolidProperties]
[steel]
type = ThermalFunctionSolidProperties
rho = 8050
k = 45
cp = 466
[]
[]
[Components]
[total_power]
type = TotalPower
power = ${tot_power}
[]
[up_pipe_1]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '0 0 1'
length = 0.5
n_elems = 15
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct1]
type = JunctionParallelChannels1Phase
position = '0 0 0.5'
connections = 'up_pipe_1:out core_chan:in'
volume = 1e-5
use_scalar_variables = false
[]
[core_chan]
type = FlowChannel1Phase
position = '0 0 0.5'
orientation = '0 0 1'
length = ${core_length}
n_elems = ${core_n_elems}
roughness = .0001
A = '${A_core}'
D_h = ${Dh_core}
[]
[core_hs]
type = HeatStructureCylindrical
position = '0 0 0.5'
orientation = '0 0 1'
length = ${core_length}
n_elems = ${core_n_elems}
names = 'block'
widths = '${fparse core_dia / 2.}'
solid_properties = 'steel'
solid_properties_T_ref = '300'
n_part_elems = 3
[]
[core_heating]
type = HeatSourceFromTotalPower
hs = core_hs
regions = block
power = total_power
[]
[core_ht]
type = HeatTransferFromHeatStructure1Phase
flow_channel = core_chan
hs = core_hs
hs_side = outer
P_hf = '${fparse pi * core_dia}'
[]
[jct2]
type = JunctionParallelChannels1Phase
position = '0 0 1.5'
connections = 'core_chan:out up_pipe_2:in'
volume = 1e-5
use_scalar_variables = false
[]
[up_pipe_2]
type = FlowChannel1Phase
position = '0 0 1.5'
orientation = '0 0 1'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct3]
type = JunctionOneToOne1Phase
connections = 'up_pipe_2:out top_pipe_1:in'
[]
[top_pipe_1]
type = FlowChannel1Phase
position = '0 0 2'
orientation = '1 0 0'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[top_pipe_2]
type = FlowChannel1Phase
position = '0.5 0 2'
orientation = '1 0 0'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct4]
type = VolumeJunction1Phase
position = '0.5 0 2'
volume = 1e-5
connections = 'top_pipe_1:out top_pipe_2:in press_pipe:in'
use_scalar_variables = false
[]
[press_pipe]
type = FlowChannel1Phase
position = '0.5 0 2'
orientation = '0 0 1'
length = 0.2
n_elems = 5
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[pressurizer]
type = InletStagnationPressureTemperature1Phase
p0 = ${press}
T0 = ${T_in}
input = press_pipe:out
[]
[jct5]
type = JunctionOneToOne1Phase
connections = 'top_pipe_2:out down_pipe_1:in'
[]
[down_pipe_1]
type = FlowChannel1Phase
position = '1 0 2'
orientation = '0 0 -1'
length = 0.25
A = ${A_pipe}
n_elems = 5
[]
[jct6]
type = JunctionOneToOne1Phase
connections = 'down_pipe_1:out cooling_pipe:in'
[]
[cooling_pipe]
type = FlowChannel1Phase
position = '1 0 1.75'
orientation = '0 0 -1'
length = 1.5
n_elems = 25
A = ${A_pipe}
[]
[cold_wall]
type = HeatTransferFromSpecifiedTemperature1Phase
flow_channel = cooling_pipe
T_wall = 300
P_hf = '${fparse pi * pipe_dia}'
[]
[jct7]
type = JunctionOneToOne1Phase
connections = 'cooling_pipe:out down_pipe_2:in'
[]
[down_pipe_2]
type = FlowChannel1Phase
position = '1 0 0.25'
orientation = '0 0 -1'
length = 0.25
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct8]
type = JunctionOneToOne1Phase
connections = 'down_pipe_2:out bottom_1:in'
[]
[bottom_1]
type = FlowChannel1Phase
position = '1 0 0'
orientation = '-1 0 0'
length = 0.5
n_elems = 5
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[pump]
type = Pump1Phase
position = '0.5 0 0'
connections = 'bottom_1:out bottom_2:in'
volume = 1e-4
A_ref = ${A_pipe}
head = 0
use_scalar_variables = false
[]
[bottom_2]
type = FlowChannel1Phase
position = '0.5 0 0'
orientation = '-1 0 0'
length = 0.5
n_elems = 5
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct10]
type = JunctionOneToOne1Phase
connections = 'bottom_2:out up_pipe_1:in'
[]
[]
[ControlLogic]
[set_point]
type = GetFunctionValueControl
function = ${m_dot_in}
[]
[pid]
type = PIDControl
initial_value = 0
set_point = set_point:value
input = m_dot_pump
K_p = 1.
K_i = 4.
K_d = 0
[]
[set_pump_head]
type = SetComponentRealValueControl
component = pump
parameter = head
value = pid:output
[]
[]
[Postprocessors]
[power_to_coolant]
type = ADHeatRateConvection1Phase
block = core_chan
P_hf = '${fparse pi *core_dia}'
[]
[m_dot_pump]
type = ADFlowJunctionFlux1Phase
boundary = core_chan:in
connection_index = 1
equation = mass
junction = jct7
[]
[core_T_out]
type = SideAverageValue
boundary = core_chan:out
variable = T
[]
[core_p_in]
type = SideAverageValue
boundary = core_chan:in
variable = p
[]
[core_p_out]
type = SideAverageValue
boundary = core_chan:out
variable = p
[]
[core_delta_p]
type = ParsedPostprocessor
pp_names = 'core_p_in core_p_out'
expression = 'core_p_in - core_p_out'
[]
[hx_pri_T_out]
type = SideAverageValue
boundary = cooling_pipe:out
variable = T
[]
[pump_head]
type = RealComponentParameterValuePostprocessor
component = pump
parameter = head
[]
[]
[Preconditioning]
[pc]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
start_time = 0
[TimeStepper]
type = IterationAdaptiveDT
dt = 1
[]
dtmax = 5
end_time = 500
line_search = basic
solve_type = NEWTON
petsc_options_iname = '-pc_type'
petsc_options_value = 'lu'
nl_rel_tol = 0
nl_abs_tol = 1e-8
nl_max_its = 25
[]
[Outputs]
exodus = true
[console]
type = Console
max_rows = 1
outlier_variable_norms = false
[]
print_linear_residuals = false
[]
(modules/thermal_hydraulics/test/tests/problems/freefall/freefall.i)
# Tests acceleration of a fluid due to gravity. The flow exiting the bottom
# of the flow channel enters the top, so the flow should uniformly accelerate
# at the rate of acceleration due to gravity.
acceleration = -10.0
dt = 0.1
num_steps = 5
time = ${fparse num_steps * dt}
# The expected velocity is the following:
# u = a * t
# = -10 * 0.5
# = -5
[GlobalParams]
gravity_vector = '0 0 ${acceleration}'
initial_p = 1e5
initial_T = 300
initial_vel = 0
scaling_factor_1phase = '1 1 1e-5'
closures = simple_closures
[]
[FluidProperties]
[fp]
type = StiffenedGasFluidProperties
gamma = 2.35
cv = 1816
q = -1.167e6
q_prime = 0
p_inf = 1e9
[]
[]
[Closures]
[simple_closures]
type = Closures1PhaseSimple
[]
[]
[Components]
[pipe]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '0 0 1'
length = 1
n_elems = 100
A = 1
f = 0
fp = fp
[]
[junction]
type = JunctionOneToOne1Phase
connections = 'pipe:in pipe:out'
[]
[]
[Preconditioning]
[pc]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
scheme = bdf2
end_time = ${time}
dt = ${dt}
num_steps = ${num_steps}
abort_on_solve_fail = true
solve_type = NEWTON
nl_abs_tol = 1e-8
nl_rel_tol = 1e-8
nl_max_its = 10
l_tol = 1e-3
l_max_its = 10
petsc_options_iname = '-pc_type'
petsc_options_value = 'lu'
[]
[Postprocessors]
[vel_avg]
type = ElementAverageValue
variable = 'vel'
execute_on = 'INITIAL TIMESTEP_END'
[]
[]
[Outputs]
velocity_as_vector = false
[out]
type = CSV
execute_on = 'FINAL'
[]
[]
(modules/thermal_hydraulics/test/tests/problems/brayton_cycle/closed_brayton_cycle.i)
# This input file is used to demonstrate a simple closed, air Brayton cycle using
# a compressor, turbine, shaft, motor, and generator.
# The flow length is divided into 6 segments as illustrated below, where
# - "(C)" denotes the compressor
# - "(T)" denotes the turbine
# - "*" denotes a fictitious junction
#
# Heated section Cooled section
# *-----(C)-----*--------------*-----(T)-----*--------------*
# 1 2 3 4 5 6
#
# Initially the fluid is at rest at ambient conditions, the shaft speed is zero,
# and no heat transfer occurs with the system.
# The transient is controlled as follows:
# * 0 - 100 s: motor ramps up torque linearly from zero
# * 100 - 200 s: motor ramps down torque linearly to zero, HTC ramps up linearly from zero.
# * 200 - 300 s: (no changes; should approach steady condition)
I_motor = 1.0
motor_torque_max = 400.0
I_generator = 1.0
generator_torque_per_shaft_speed = -0.00025
motor_ramp_up_duration = 100.0
motor_ramp_down_duration = 100.0
post_motor_time = 100.0
t1 = ${motor_ramp_up_duration}
t2 = ${fparse t1 + motor_ramp_down_duration}
t3 = ${fparse t2 + post_motor_time}
D1 = 0.15
D2 = ${D1}
D3 = ${D1}
D4 = ${D1}
D5 = ${D1}
D6 = ${D1}
A1 = ${fparse 0.25 * pi * D1^2}
A2 = ${fparse 0.25 * pi * D2^2}
A3 = ${fparse 0.25 * pi * D3^2}
A4 = ${fparse 0.25 * pi * D4^2}
A5 = ${fparse 0.25 * pi * D5^2}
A6 = ${fparse 0.25 * pi * D6^2}
L1 = 10.0
L2 = ${L1}
L3 = ${L1}
L4 = ${L1}
L5 = ${L1}
L6 = ${L1}
x1 = 0.0
x2 = ${fparse x1 + L1}
x3 = ${fparse x2 + L2}
x4 = ${fparse x3 + L3}
x5 = ${fparse x4 + L4}
x6 = ${fparse x5 + L5}
x2_minus = ${fparse x2 - 0.001}
x2_plus = ${fparse x2 + 0.001}
x5_minus = ${fparse x5 - 0.001}
x5_plus = ${fparse x5 + 0.001}
n_elems1 = 10
n_elems2 = ${n_elems1}
n_elems3 = ${n_elems1}
n_elems4 = ${n_elems1}
n_elems5 = ${n_elems1}
n_elems6 = ${n_elems1}
A_ref_comp = ${fparse 0.5 * (A1 + A2)}
V_comp = ${fparse A_ref_comp * 1.0}
I_comp = 1.0
A_ref_turb = ${fparse 0.5 * (A4 + A5)}
V_turb = ${fparse A_ref_turb * 1.0}
I_turb = 1.0
c0_rated_comp = 351.6925137
rho0_rated_comp = 1.146881112
rated_mfr = 0.25
speed_rated_rpm = 96000
speed_rated = ${fparse speed_rated_rpm * 2 * pi / 60.0}
speed_initial = 0
eff_comp = 0.79
eff_turb = 0.843
T_hot = 1000
T_cold = 300
T_ambient = 300
p_ambient = 1e5
[GlobalParams]
orientation = '1 0 0'
gravity_vector = '0 0 0'
initial_p = ${p_ambient}
initial_T = ${T_ambient}
initial_vel = 0
initial_vel_x = 0
initial_vel_y = 0
initial_vel_z = 0
fp = fp_air
closures = closures
f = 0
scaling_factor_1phase = '1 1 1e-5'
scaling_factor_rhoV = 1
scaling_factor_rhouV = 1
scaling_factor_rhovV = 1
scaling_factor_rhowV = 1
scaling_factor_rhoEV = 1e-5
rdg_slope_reconstruction = none
[]
[Functions]
[motor_torque_fn]
type = PiecewiseLinear
x = '0 ${t1} ${t2}'
y = '0 ${motor_torque_max} 0'
[]
[motor_power_fn]
type = ParsedFunction
expression = 'torque * speed'
symbol_names = 'torque speed'
symbol_values = 'motor_torque shaft:omega'
[]
[generator_torque_fn]
type = ParsedFunction
expression = 'slope * t'
symbol_names = 'slope'
symbol_values = '${generator_torque_per_shaft_speed}'
[]
[generator_power_fn]
type = ParsedFunction
expression = 'torque * speed'
symbol_names = 'torque speed'
symbol_values = 'generator_torque shaft:omega'
[]
[htc_wall_fn]
type = PiecewiseLinear
x = '0 ${t1} ${t2}'
y = '0 0 1e3'
[]
[]
[FluidProperties]
[fp_air]
type = IdealGasFluidProperties
emit_on_nan = none
[]
[]
[Closures]
[closures]
type = Closures1PhaseSimple
[]
[]
[Components]
[shaft]
type = Shaft
connected_components = 'motor compressor turbine generator'
initial_speed = ${speed_initial}
[]
[motor]
type = ShaftConnectedMotor
inertia = ${I_motor}
torque = 0 # controlled
[]
[generator]
type = ShaftConnectedMotor
inertia = ${I_generator}
torque = generator_torque_fn
[]
[pipe1]
type = FlowChannel1Phase
position = '${x1} 0 0'
length = ${L1}
n_elems = ${n_elems1}
A = ${A1}
[]
[compressor]
type = ShaftConnectedCompressor1Phase
position = '${x2} 0 0'
inlet = 'pipe1:out'
outlet = 'pipe2:in'
A_ref = ${A_ref_comp}
volume = ${V_comp}
omega_rated = ${speed_rated}
mdot_rated = ${rated_mfr}
c0_rated = ${c0_rated_comp}
rho0_rated = ${rho0_rated_comp}
speeds = '0.5208 0.6250 0.7292 0.8333 0.9375'
Rp_functions = 'rp_comp1 rp_comp2 rp_comp3 rp_comp4 rp_comp5'
eff_functions = 'eff_comp1 eff_comp2 eff_comp3 eff_comp4 eff_comp5'
min_pressure_ratio = 1.0
speed_cr_I = 0
inertia_const = ${I_comp}
inertia_coeff = '${I_comp} 0 0 0'
# assume no shaft friction
speed_cr_fr = 0
tau_fr_const = 0
tau_fr_coeff = '0 0 0 0'
use_scalar_variables = false
[]
[pipe2]
type = FlowChannel1Phase
position = '${x2} 0 0'
length = ${L2}
n_elems = ${n_elems2}
A = ${A2}
[]
[junction2_3]
type = JunctionOneToOne1Phase
connections = 'pipe2:out pipe3:in'
[]
[pipe3]
type = FlowChannel1Phase
position = '${x3} 0 0'
length = ${L3}
n_elems = ${n_elems3}
A = ${A3}
[]
[junction3_4]
type = JunctionOneToOne1Phase
connections = 'pipe3:out pipe4:in'
[]
[pipe4]
type = FlowChannel1Phase
position = '${x4} 0 0'
length = ${L4}
n_elems = ${n_elems4}
A = ${A4}
[]
[turbine]
type = ShaftConnectedCompressor1Phase
position = '${x5} 0 0'
inlet = 'pipe4:out'
outlet = 'pipe5:in'
A_ref = ${A_ref_turb}
volume = ${V_turb}
treat_as_turbine = true
omega_rated = ${speed_rated}
mdot_rated = ${rated_mfr}
c0_rated = ${c0_rated_comp}
rho0_rated = ${rho0_rated_comp}
speeds = '0 0.5208 0.6250 0.7292 0.8333 0.9375'
Rp_functions = 'rp_turb0 rp_turb1 rp_turb2 rp_turb3 rp_turb4 rp_turb5'
eff_functions = 'eff_turb1 eff_turb1 eff_turb2 eff_turb3 eff_turb4 eff_turb5'
min_pressure_ratio = 1.0
speed_cr_I = 0
inertia_const = ${I_turb}
inertia_coeff = '${I_turb} 0 0 0'
# assume no shaft friction
speed_cr_fr = 0
tau_fr_const = 0
tau_fr_coeff = '0 0 0 0'
use_scalar_variables = false
[]
[pipe5]
type = FlowChannel1Phase
position = '${x5} 0 0'
length = ${L5}
n_elems = ${n_elems5}
A = ${A5}
[]
[junction5_6]
type = JunctionOneToOne1Phase
connections = 'pipe5:out pipe6:in'
[]
[pipe6]
type = FlowChannel1Phase
position = '${x6} 0 0'
length = ${L6}
n_elems = ${n_elems6}
A = ${A6}
[]
[junction6_1]
type = JunctionOneToOne1Phase
connections = 'pipe6:out pipe1:in'
[]
[heating]
type = HeatTransferFromSpecifiedTemperature1Phase
flow_channel = pipe3
T_wall = ${T_hot}
Hw = htc_wall_fn
[]
[cooling]
type = HeatTransferFromSpecifiedTemperature1Phase
flow_channel = pipe6
T_wall = ${T_cold}
Hw = htc_wall_fn
[]
[]
[ControlLogic]
[motor_ctrl]
type = TimeFunctionComponentControl
component = motor
parameter = torque
function = motor_torque_fn
[]
[]
[Postprocessors]
[heating_rate]
type = ADHeatRateConvection1Phase
block = 'pipe3'
T = T
T_wall = T_wall
Hw = Hw
P_hf = P_hf
execute_on = 'INITIAL TIMESTEP_END'
[]
[cooling_rate]
type = ADHeatRateConvection1Phase
block = 'pipe6'
T = T
T_wall = T_wall
Hw = Hw
P_hf = P_hf
execute_on = 'INITIAL TIMESTEP_END'
[]
[motor_torque]
type = RealComponentParameterValuePostprocessor
component = motor
parameter = torque
execute_on = 'INITIAL TIMESTEP_END'
[]
[motor_power]
type = FunctionValuePostprocessor
function = motor_power_fn
execute_on = 'INITIAL TIMESTEP_END'
indirect_dependencies = 'motor_torque shaft:omega'
[]
[generator_torque]
type = ShaftConnectedComponentPostprocessor
quantity = torque
shaft_connected_component_uo = generator:shaftconnected_uo
execute_on = 'INITIAL TIMESTEP_END'
[]
[generator_power]
type = FunctionValuePostprocessor
function = generator_power_fn
execute_on = 'INITIAL TIMESTEP_END'
indirect_dependencies = 'generator_torque shaft:omega'
[]
[shaft_speed]
type = ScalarVariable
variable = 'shaft:omega'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_in_comp]
type = PointValue
variable = p
point = '${x2_minus} 0 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_out_comp]
type = PointValue
variable = p
point = '${x2_plus} 0 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_ratio_comp]
type = ParsedPostprocessor
pp_names = 'p_in_comp p_out_comp'
expression = 'p_out_comp / p_in_comp'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_in_turb]
type = PointValue
variable = p
point = '${x5_minus} 0 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_out_turb]
type = PointValue
variable = p
point = '${x5_plus} 0 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_ratio_turb]
type = ParsedPostprocessor
pp_names = 'p_in_turb p_out_turb'
expression = 'p_in_turb / p_out_turb'
execute_on = 'INITIAL TIMESTEP_END'
[]
[mfr_comp]
type = ADFlowJunctionFlux1Phase
boundary = pipe1:out
connection_index = 0
equation = mass
junction = compressor
[]
[mfr_turb]
type = ADFlowJunctionFlux1Phase
boundary = pipe4:out
connection_index = 0
equation = mass
junction = turbine
[]
[]
[Preconditioning]
[pc]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
scheme = 'bdf2'
end_time = ${t3}
dt = 0.1
abort_on_solve_fail = true
solve_type = NEWTON
nl_rel_tol = 1e-50
nl_abs_tol = 1e-11
nl_max_its = 15
l_tol = 1e-4
l_max_its = 10
[]
[Outputs]
[csv]
type = CSV
file_base = 'closed_brayton_cycle'
execute_vector_postprocessors_on = 'INITIAL'
[]
[console]
type = Console
show = 'shaft_speed p_ratio_comp p_ratio_turb compressor:pressure_ratio turbine:pressure_ratio'
[]
[]
[Functions]
# compressor pressure ratio
[rp_comp1]
type = PiecewiseLinear
data_file = 'rp_comp1.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp2]
type = PiecewiseLinear
data_file = 'rp_comp2.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp3]
type = PiecewiseLinear
data_file = 'rp_comp3.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp4]
type = PiecewiseLinear
data_file = 'rp_comp4.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp5]
type = PiecewiseLinear
data_file = 'rp_comp5.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
# compressor efficiency
[eff_comp1]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp2]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp3]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp4]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp5]
type = ConstantFunction
value = ${eff_comp}
[]
# turbine pressure ratio
[rp_turb0]
type = ConstantFunction
value = 1
[]
[rp_turb1]
type = PiecewiseLinear
data_file = 'rp_turb1.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb2]
type = PiecewiseLinear
data_file = 'rp_turb2.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb3]
type = PiecewiseLinear
data_file = 'rp_turb3.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb4]
type = PiecewiseLinear
data_file = 'rp_turb4.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb5]
type = PiecewiseLinear
data_file = 'rp_turb5.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
# turbine efficiency
[eff_turb1]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb2]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb3]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb4]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb5]
type = ConstantFunction
value = ${eff_turb}
[]
[]
(modules/thermal_hydraulics/tutorials/single_phase_flow/06_custom_closures.i)
T_in = 300. # K
m_dot_in = 1e-2 # kg/s
press = 10e5 # Pa
# core parameters
core_length = 1. # m
core_n_elems = 25
core_dia = '${units 2. cm -> m}'
core_pitch = '${units 8.7 cm -> m}'
A_core = '${fparse core_pitch^2 - 0.25 *pi * core_dia^2}'
P_wet_core = '${fparse 4*core_pitch + pi * core_dia}'
Dh_core = '${fparse 4 * A_core / P_wet_core}'
# pipe parameters
pipe_dia = '${units 10. cm -> m}'
A_pipe = '${fparse 0.25 * pi * pipe_dia^2}'
tot_power = 2000 # W
# heat exchanger parameters
hx_dia_inner = '${units 12. cm -> m}'
hx_wall_thickness = '${units 5. mm -> m}'
hx_dia_outer = '${units 50. cm -> m}'
hx_radius_wall = '${fparse hx_dia_inner / 2. + hx_wall_thickness}'
hx_length = 1.5 # m
hx_n_elems = 25
m_dot_sec_in = 1. # kg/s
[GlobalParams]
initial_p = ${press}
initial_vel = 0.0001
initial_T = ${T_in}
initial_vel_x = 0
initial_vel_y = 0
initial_vel_z = 0
gravity_vector = '0 0 0'
rdg_slope_reconstruction = minmod
scaling_factor_1phase = '1 1e-2 1e-4'
scaling_factor_rhoV = 1
scaling_factor_rhouV = 1e-2
scaling_factor_rhovV = 1e-2
scaling_factor_rhowV = 1e-2
scaling_factor_rhoEV = 1e-4
closures = thm_closures
fp = he
[]
[Functions]
[m_dot_sec_fn]
type = PiecewiseLinear
xy_data = '
0 0
10 ${m_dot_sec_in}'
[]
[]
[FluidProperties]
[he]
type = IdealGasFluidProperties
molar_mass = 4e-3
gamma = 1.67
k = 0.2556
mu = 3.22639e-5
[]
[water]
type = StiffenedGasFluidProperties
gamma = 2.35
cv = 1816.0
q = -1.167e6
p_inf = 1.0e9
q_prime = 0
[]
[]
[Closures]
[thm_closures]
type = Closures1PhaseTHM
[]
[none_closures]
type = Closures1PhaseNone
[]
[]
[Materials]
[Re_mat]
type = ADReynoldsNumberMaterial
Re = Re
rho = rho
vel = vel
D_h = D_h
mu = mu
block = hx/pri
[]
[f_mat]
type = ADParsedMaterial
property_name = f_D
constant_names = 'a b c'
constant_expressions = '1 0.1 -0.5'
material_property_names = 'Re'
expression = 'a + b * Re^c'
block = hx/pri
[]
[Pr_mat]
type = ADPrandtlNumberMaterial
Pr = Pr
cp = cp
mu = mu
k = k
block = hx/pri
[]
[Nu_mat]
type = ADParsedMaterial
property_name = 'Nu'
constant_names = 'a b c'
constant_expressions = '0.03 0.9 0.5'
material_property_names = 'Re Pr'
expression = 'a * Re ^b * Pr^c'
block = hx/pri
[]
[Hw_mat]
type = ADConvectiveHeatTransferCoefficientMaterial
D_h = D_h
k = k
Nu = Nu
Hw = Hw
block = hx/pri
[]
[]
[SolidProperties]
[steel]
type = ThermalFunctionSolidProperties
rho = 8050
k = 45
cp = 466
[]
[]
[Components]
[total_power]
type = TotalPower
power = ${tot_power}
[]
[up_pipe_1]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '0 0 1'
length = 0.5
n_elems = 15
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct1]
type = JunctionParallelChannels1Phase
position = '0 0 0.5'
connections = 'up_pipe_1:out core_chan:in'
volume = 1e-5
use_scalar_variables = false
[]
[core_chan]
type = FlowChannel1Phase
position = '0 0 0.5'
orientation = '0 0 1'
length = ${core_length}
n_elems = ${core_n_elems}
roughness = .0001
A = ${A_core}
D_h = ${Dh_core}
[]
[core_hs]
type = HeatStructureCylindrical
position = '0 0 0.5'
orientation = '0 0 1'
length = ${core_length}
n_elems = ${core_n_elems}
names = 'block'
widths = '${fparse core_dia / 2.}'
solid_properties = 'steel'
solid_properties_T_ref = '300'
n_part_elems = 3
[]
[core_heating]
type = HeatSourceFromTotalPower
hs = core_hs
regions = block
power = total_power
[]
[core_ht]
type = HeatTransferFromHeatStructure1Phase
flow_channel = core_chan
hs = core_hs
hs_side = outer
P_hf = '${fparse pi * core_dia}'
[]
[jct2]
type = JunctionParallelChannels1Phase
position = '0 0 1.5'
connections = 'core_chan:out up_pipe_2:in'
volume = 1e-5
use_scalar_variables = false
[]
[up_pipe_2]
type = FlowChannel1Phase
position = '0 0 1.5'
orientation = '0 0 1'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct3]
type = JunctionOneToOne1Phase
connections = 'up_pipe_2:out top_pipe_1:in'
[]
[top_pipe_1]
type = FlowChannel1Phase
position = '0 0 2'
orientation = '1 0 0'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[top_pipe_2]
type = FlowChannel1Phase
position = '0.5 0 2'
orientation = '1 0 0'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct4]
type = VolumeJunction1Phase
position = '0.5 0 2'
volume = 1e-5
connections = 'top_pipe_1:out top_pipe_2:in press_pipe:in'
use_scalar_variables = false
[]
[press_pipe]
type = FlowChannel1Phase
position = '0.5 0 2'
orientation = '0 1 0'
length = 0.2
n_elems = 5
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[pressurizer]
type = InletStagnationPressureTemperature1Phase
p0 = ${press}
T0 = ${T_in}
input = press_pipe:out
[]
[jct5]
type = JunctionOneToOne1Phase
connections = 'top_pipe_2:out down_pipe_1:in'
[]
[down_pipe_1]
type = FlowChannel1Phase
position = '1 0 2'
orientation = '0 0 -1'
length = 0.25
A = ${A_pipe}
n_elems = 5
[]
[jct6]
type = JunctionParallelChannels1Phase
position = '1 0 1.75'
connections = 'down_pipe_1:out hx/pri:in'
volume = 1e-5
use_scalar_variables = false
[]
[hx]
[pri]
type = FlowChannel1Phase
position = '1 0 1.75'
orientation = '0 0 -1'
length = ${hx_length}
n_elems = ${hx_n_elems}
roughness = 1e-5
A = '${fparse pi * hx_dia_inner * hx_dia_inner / 4.}'
D_h = ${hx_dia_inner}
closures = none_closures
[]
[ht_pri]
type = HeatTransferFromHeatStructure1Phase
hs = hx/wall
hs_side = inner
flow_channel = hx/pri
P_hf = '${fparse pi * hx_dia_inner}'
[]
[wall]
type = HeatStructureCylindrical
position = '1 0 1.75'
orientation = '0 0 -1'
length = ${hx_length}
n_elems = ${hx_n_elems}
widths = '${hx_wall_thickness}'
n_part_elems = '3'
solid_properties = 'steel'
solid_properties_T_ref = '300'
names = '0'
inner_radius = '${fparse hx_dia_inner / 2.}'
[]
[ht_sec]
type = HeatTransferFromHeatStructure1Phase
hs = hx/wall
hs_side = outer
flow_channel = hx/sec
P_hf = '${fparse 2 * pi * hx_radius_wall}'
[]
[sec]
type = FlowChannel1Phase
position = '${fparse 1 + hx_wall_thickness} 0 0.25'
orientation = '0 0 1'
length = ${hx_length}
n_elems = ${hx_n_elems}
A = '${fparse pi * (hx_dia_outer * hx_dia_outer / 4. - hx_radius_wall * hx_radius_wall)}'
D_h = '${fparse hx_dia_outer - (2 * hx_radius_wall)}'
fp = water
initial_T = 300
[]
[]
[jct7]
type = JunctionParallelChannels1Phase
position = '1 0 0.5'
connections = 'hx/pri:out down_pipe_2:in'
volume = 1e-5
use_scalar_variables = false
[]
[down_pipe_2]
type = FlowChannel1Phase
position = '1 0 0.25'
orientation = '0 0 -1'
length = 0.25
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct8]
type = JunctionOneToOne1Phase
connections = 'down_pipe_2:out bottom_1:in'
[]
[bottom_1]
type = FlowChannel1Phase
position = '1 0 0'
orientation = '-1 0 0'
length = 0.5
n_elems = 5
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[pump]
type = Pump1Phase
position = '0.5 0 0'
connections = 'bottom_1:out bottom_2:in'
volume = 1e-4
A_ref = ${A_pipe}
head = 0
use_scalar_variables = false
[]
[bottom_2]
type = FlowChannel1Phase
position = '0.5 0 0'
orientation = '-1 0 0'
length = 0.5
n_elems = 5
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct9]
type = JunctionOneToOne1Phase
connections = 'bottom_2:out up_pipe_1:in'
[]
[inlet_sec]
type = InletMassFlowRateTemperature1Phase
input = 'hx/sec:in'
m_dot = 0
T = 300
[]
[outlet_sec]
type = Outlet1Phase
input = 'hx/sec:out'
p = 1e5
[]
[]
[ControlLogic]
[set_point]
type = GetFunctionValueControl
function = ${m_dot_in}
[]
[pid]
type = PIDControl
initial_value = 0.0
set_point = set_point:value
input = m_dot_pump
K_p = 1.
K_i = 4.
K_d = 0
[]
[set_pump_head]
type = SetComponentRealValueControl
component = pump
parameter = head
value = pid:output
[]
[m_dot_sec_inlet_ctrl]
type = GetFunctionValueControl
function = m_dot_sec_fn
[]
[set_m_dot_sec_ctrl]
type = SetComponentRealValueControl
component = inlet_sec
parameter = m_dot
value = m_dot_sec_inlet_ctrl:value
[]
[]
[Postprocessors]
[power_to_coolant]
type = ADHeatRateConvection1Phase
block = core_chan
P_hf = '${fparse pi *core_dia}'
[]
[m_dot_pump]
type = ADFlowJunctionFlux1Phase
boundary = core_chan:in
connection_index = 1
equation = mass
junction = jct7
[]
[core_T_out]
type = SideAverageValue
boundary = core_chan:out
variable = T
[]
[core_p_in]
type = SideAverageValue
boundary = core_chan:in
variable = p
[]
[core_p_out]
type = SideAverageValue
boundary = core_chan:out
variable = p
[]
[core_delta_p]
type = ParsedPostprocessor
pp_names = 'core_p_in core_p_out'
expression = 'core_p_in - core_p_out'
[]
[hx_pri_T_out]
type = SideAverageValue
boundary = hx/pri:out
variable = T
[]
[hx_sec_T_in]
type = SideAverageValue
boundary = inlet_sec
variable = T
[]
[hx_sec_T_out]
type = SideAverageValue
boundary = outlet_sec
variable = T
[]
[m_dot_sec]
type = ADFlowBoundaryFlux1Phase
boundary = inlet_sec
equation = mass
[]
[Hw_hx_pri]
type = ADElementAverageMaterialProperty
mat_prop = Hw
block = hx/pri
[]
[fD_hx_pri]
type = ADElementAverageMaterialProperty
mat_prop = f_D
block = hx/pri
[]
[]
[Preconditioning]
[pc]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
start_time = 0
[TimeStepper]
type = IterationAdaptiveDT
dt = 1
[]
dtmax = 5
end_time = 500
line_search = basic
solve_type = NEWTON
petsc_options_iname = '-pc_type'
petsc_options_value = 'lu'
nl_rel_tol = 1e-8
nl_abs_tol = 1e-8
nl_max_its = 25
[]
[Outputs]
exodus = true
[console]
type = Console
max_rows = 1
outlier_variable_norms = false
[]
print_linear_residuals = false
[]
(modules/thermal_hydraulics/test/tests/problems/brayton_cycle/open_brayton_cycle.i)
# This input file is used to demonstrate a simple open-air Brayton cycle using
# a compressor, turbine, shaft, motor, and generator.
# The flow length is divided into 5 segments as illustrated below, where
# - "(I)" denotes the inlet
# - "(C)" denotes the compressor
# - "(T)" denotes the turbine
# - "(O)" denotes the outlet
# - "*" denotes a fictitious junction
#
# Heated section
# (I)-----(C)-----*--------------*-----(T)-----(O)
# 1 2 3 4 5
#
# Initially the fluid is at rest at ambient conditions, the shaft speed is zero,
# and no heat transfer occurs with the system.
# The transient is controlled as follows:
# * 0 - 100 s: motor ramps up torque linearly from zero
# * 100 - 200 s: motor ramps down torque linearly to zero, HTC ramps up linearly from zero.
# * 200 - 300 s: (no changes; should approach steady condition)
I_motor = 1.0
motor_torque_max = 400.0
I_generator = 1.0
generator_torque_per_shaft_speed = -0.00025
motor_ramp_up_duration = 100.0
motor_ramp_down_duration = 100.0
post_motor_time = 100.0
t1 = ${motor_ramp_up_duration}
t2 = ${fparse t1 + motor_ramp_down_duration}
t3 = ${fparse t2 + post_motor_time}
D1 = 0.15
D2 = ${D1}
D3 = ${D1}
D4 = ${D1}
D5 = ${D1}
A1 = ${fparse 0.25 * pi * D1^2}
A2 = ${fparse 0.25 * pi * D2^2}
A3 = ${fparse 0.25 * pi * D3^2}
A4 = ${fparse 0.25 * pi * D4^2}
A5 = ${fparse 0.25 * pi * D5^2}
L1 = 10.0
L2 = ${L1}
L3 = ${L1}
L4 = ${L1}
L5 = ${L1}
x1 = 0.0
x2 = ${fparse x1 + L1}
x3 = ${fparse x2 + L2}
x4 = ${fparse x3 + L3}
x5 = ${fparse x4 + L4}
x2_minus = ${fparse x2 - 0.001}
x2_plus = ${fparse x2 + 0.001}
x5_minus = ${fparse x5 - 0.001}
x5_plus = ${fparse x5 + 0.001}
n_elems1 = 10
n_elems2 = ${n_elems1}
n_elems3 = ${n_elems1}
n_elems4 = ${n_elems1}
n_elems5 = ${n_elems1}
A_ref_comp = ${fparse 0.5 * (A1 + A2)}
V_comp = ${fparse A_ref_comp * 1.0}
I_comp = 1.0
A_ref_turb = ${fparse 0.5 * (A4 + A5)}
V_turb = ${fparse A_ref_turb * 1.0}
I_turb = 1.0
c0_rated_comp = 351.6925137
rho0_rated_comp = 1.146881112
rated_mfr = 0.25
speed_rated_rpm = 96000
speed_rated = ${fparse speed_rated_rpm * 2 * pi / 60.0}
speed_initial = 0
eff_comp = 0.79
eff_turb = 0.843
T_hot = 1000
T_ambient = 300
p_ambient = 1e5
[GlobalParams]
orientation = '1 0 0'
gravity_vector = '0 0 0'
initial_p = ${p_ambient}
initial_T = ${T_ambient}
initial_vel = 0
initial_vel_x = 0
initial_vel_y = 0
initial_vel_z = 0
fp = fp_air
closures = closures
f = 0
scaling_factor_1phase = '1 1 1e-5'
scaling_factor_rhoV = 1
scaling_factor_rhouV = 1
scaling_factor_rhovV = 1
scaling_factor_rhowV = 1
scaling_factor_rhoEV = 1e-5
rdg_slope_reconstruction = none
[]
[Functions]
[motor_torque_fn]
type = PiecewiseLinear
x = '0 ${t1} ${t2}'
y = '0 ${motor_torque_max} 0'
[]
[motor_power_fn]
type = ParsedFunction
expression = 'torque * speed'
symbol_names = 'torque speed'
symbol_values = 'motor_torque shaft:omega'
[]
[generator_torque_fn]
type = ParsedFunction
expression = 'slope * t'
symbol_names = 'slope'
symbol_values = '${generator_torque_per_shaft_speed}'
[]
[generator_power_fn]
type = ParsedFunction
expression = 'torque * speed'
symbol_names = 'torque speed'
symbol_values = 'generator_torque shaft:omega'
[]
[htc_wall_fn]
type = PiecewiseLinear
x = '0 ${t1} ${t2}'
y = '0 0 1e3'
[]
[]
[FluidProperties]
[fp_air]
type = IdealGasFluidProperties
emit_on_nan = none
[]
[]
[Closures]
[closures]
type = Closures1PhaseSimple
[]
[]
[Components]
[shaft]
type = Shaft
connected_components = 'motor compressor turbine generator'
initial_speed = ${speed_initial}
[]
[motor]
type = ShaftConnectedMotor
inertia = ${I_motor}
torque = 0 # controlled
[]
[generator]
type = ShaftConnectedMotor
inertia = ${I_generator}
torque = generator_torque_fn
[]
[inlet]
type = InletStagnationPressureTemperature1Phase
input = 'pipe1:in'
p0 = ${p_ambient}
T0 = ${T_ambient}
[]
[pipe1]
type = FlowChannel1Phase
position = '${x1} 0 0'
length = ${L1}
n_elems = ${n_elems1}
A = ${A1}
[]
[compressor]
type = ShaftConnectedCompressor1Phase
position = '${x2} 0 0'
inlet = 'pipe1:out'
outlet = 'pipe2:in'
A_ref = ${A_ref_comp}
volume = ${V_comp}
omega_rated = ${speed_rated}
mdot_rated = ${rated_mfr}
c0_rated = ${c0_rated_comp}
rho0_rated = ${rho0_rated_comp}
speeds = '0.5208 0.6250 0.7292 0.8333 0.9375'
Rp_functions = 'rp_comp1 rp_comp2 rp_comp3 rp_comp4 rp_comp5'
eff_functions = 'eff_comp1 eff_comp2 eff_comp3 eff_comp4 eff_comp5'
min_pressure_ratio = 1.0
speed_cr_I = 0
inertia_const = ${I_comp}
inertia_coeff = '${I_comp} 0 0 0'
# assume no shaft friction
speed_cr_fr = 0
tau_fr_const = 0
tau_fr_coeff = '0 0 0 0'
use_scalar_variables = false
[]
[pipe2]
type = FlowChannel1Phase
position = '${x2} 0 0'
length = ${L2}
n_elems = ${n_elems2}
A = ${A2}
[]
[junction2_3]
type = JunctionOneToOne1Phase
connections = 'pipe2:out pipe3:in'
[]
[pipe3]
type = FlowChannel1Phase
position = '${x3} 0 0'
length = ${L3}
n_elems = ${n_elems3}
A = ${A3}
[]
[junction3_4]
type = JunctionOneToOne1Phase
connections = 'pipe3:out pipe4:in'
[]
[pipe4]
type = FlowChannel1Phase
position = '${x4} 0 0'
length = ${L4}
n_elems = ${n_elems4}
A = ${A4}
[]
[turbine]
type = ShaftConnectedCompressor1Phase
position = '${x5} 0 0'
inlet = 'pipe4:out'
outlet = 'pipe5:in'
A_ref = ${A_ref_turb}
volume = ${V_turb}
treat_as_turbine = true
omega_rated = ${speed_rated}
mdot_rated = ${rated_mfr}
c0_rated = ${c0_rated_comp}
rho0_rated = ${rho0_rated_comp}
speeds = '0 0.5208 0.6250 0.7292 0.8333 0.9375'
Rp_functions = 'rp_turb0 rp_turb1 rp_turb2 rp_turb3 rp_turb4 rp_turb5'
eff_functions = 'eff_turb1 eff_turb1 eff_turb2 eff_turb3 eff_turb4 eff_turb5'
min_pressure_ratio = 1.0
speed_cr_I = 0
inertia_const = ${I_turb}
inertia_coeff = '${I_turb} 0 0 0'
# assume no shaft friction
speed_cr_fr = 0
tau_fr_const = 0
tau_fr_coeff = '0 0 0 0'
use_scalar_variables = false
[]
[pipe5]
type = FlowChannel1Phase
position = '${x5} 0 0'
length = ${L5}
n_elems = ${n_elems5}
A = ${A5}
[]
[outlet]
type = Outlet1Phase
input = 'pipe5:out'
p = ${p_ambient}
[]
[heating]
type = HeatTransferFromSpecifiedTemperature1Phase
flow_channel = pipe3
T_wall = ${T_hot}
Hw = htc_wall_fn
[]
[]
[ControlLogic]
[motor_ctrl]
type = TimeFunctionComponentControl
component = motor
parameter = torque
function = motor_torque_fn
[]
[]
[Postprocessors]
[heating_rate]
type = ADHeatRateConvection1Phase
block = 'pipe3'
T = T
T_wall = T_wall
Hw = Hw
P_hf = P_hf
execute_on = 'INITIAL TIMESTEP_END'
[]
[motor_torque]
type = RealComponentParameterValuePostprocessor
component = motor
parameter = torque
execute_on = 'INITIAL TIMESTEP_END'
[]
[motor_power]
type = FunctionValuePostprocessor
function = motor_power_fn
execute_on = 'INITIAL TIMESTEP_END'
indirect_dependencies = 'motor_torque shaft:omega'
[]
[generator_torque]
type = ShaftConnectedComponentPostprocessor
quantity = torque
shaft_connected_component_uo = generator:shaftconnected_uo
execute_on = 'INITIAL TIMESTEP_END'
[]
[generator_power]
type = FunctionValuePostprocessor
function = generator_power_fn
execute_on = 'INITIAL TIMESTEP_END'
indirect_dependencies = 'generator_torque shaft:omega'
[]
[shaft_speed]
type = ScalarVariable
variable = 'shaft:omega'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_in_comp]
type = PointValue
variable = p
point = '${x2_minus} 0 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_out_comp]
type = PointValue
variable = p
point = '${x2_plus} 0 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_ratio_comp]
type = ParsedPostprocessor
pp_names = 'p_in_comp p_out_comp'
expression = 'p_out_comp / p_in_comp'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_in_turb]
type = PointValue
variable = p
point = '${x5_minus} 0 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_out_turb]
type = PointValue
variable = p
point = '${x5_plus} 0 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_ratio_turb]
type = ParsedPostprocessor
pp_names = 'p_in_turb p_out_turb'
expression = 'p_in_turb / p_out_turb'
execute_on = 'INITIAL TIMESTEP_END'
[]
[mfr_comp]
type = ADFlowJunctionFlux1Phase
boundary = pipe1:out
connection_index = 0
equation = mass
junction = compressor
[]
[mfr_turb]
type = ADFlowJunctionFlux1Phase
boundary = pipe4:out
connection_index = 0
equation = mass
junction = turbine
[]
[]
[Preconditioning]
[pc]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
scheme = 'bdf2'
end_time = ${t3}
dt = 0.1
abort_on_solve_fail = true
solve_type = NEWTON
nl_rel_tol = 1e-50
nl_abs_tol = 1e-11
nl_max_its = 15
l_tol = 1e-4
l_max_its = 10
[]
[Outputs]
[csv]
type = CSV
file_base = 'open_brayton_cycle'
execute_vector_postprocessors_on = 'INITIAL'
[]
[console]
type = Console
show = 'shaft_speed p_ratio_comp p_ratio_turb compressor:pressure_ratio turbine:pressure_ratio'
[]
[]
[Functions]
# compressor pressure ratio
[rp_comp1]
type = PiecewiseLinear
data_file = 'rp_comp1.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp2]
type = PiecewiseLinear
data_file = 'rp_comp2.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp3]
type = PiecewiseLinear
data_file = 'rp_comp3.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp4]
type = PiecewiseLinear
data_file = 'rp_comp4.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp5]
type = PiecewiseLinear
data_file = 'rp_comp5.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
# compressor efficiency
[eff_comp1]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp2]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp3]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp4]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp5]
type = ConstantFunction
value = ${eff_comp}
[]
# turbine pressure ratio
[rp_turb0]
type = ConstantFunction
value = 1
[]
[rp_turb1]
type = PiecewiseLinear
data_file = 'rp_turb1.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb2]
type = PiecewiseLinear
data_file = 'rp_turb2.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb3]
type = PiecewiseLinear
data_file = 'rp_turb3.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb4]
type = PiecewiseLinear
data_file = 'rp_turb4.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb5]
type = PiecewiseLinear
data_file = 'rp_turb5.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
# turbine efficiency
[eff_turb1]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb2]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb3]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb4]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb5]
type = ConstantFunction
value = ${eff_turb}
[]
[]
(modules/thermal_hydraulics/test/tests/problems/area_constriction/area_constriction_junction.i)
# This test features air flowing through a channel whose cross-sectional area
# shrinks to half its value in the right half. Assuming incompressible flow
# conditions, such as having a low Mach number, the velocity should approximately
# double from inlet to outlet. In this version of the test, the area discontinuity
# is achieved by connecting two flow channels with a junction.
p_outlet = 1e5
[GlobalParams]
gravity_vector = '0 0 0'
initial_T = 300
initial_p = ${p_outlet}
fp = fp
closures = simple_closures
f = 0
scaling_factor_1phase = '1 1 1e-5'
[]
[FluidProperties]
[fp]
type = IdealGasFluidProperties
gamma = 1.4
[]
[]
[Closures]
[simple_closures]
type = Closures1PhaseSimple
[]
[]
[Components]
[inlet]
type = InletDensityVelocity1Phase
input = 'pipe1:in'
rho = 1.16263315948279 # rho @ (p = 1e5 Pa, T = 300 K)
vel = 1
[]
[pipe1]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '1 0 0'
length = 0.5
n_elems = 50
A = 1
initial_vel = 1
[]
[junction]
type = JunctionOneToOne1Phase
connections = 'pipe1:out pipe2:in'
[]
[pipe2]
type = FlowChannel1Phase
position = '0.5 0 0'
orientation = '1 0 0'
length = 0.5
n_elems = 50
A = 0.5
initial_vel = 2
[]
[outlet]
type = Outlet1Phase
input = 'pipe2:out'
p = ${p_outlet}
[]
[]
[Preconditioning]
[pc]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
scheme = 'bdf2'
end_time = 10
[TimeStepper]
type = IterationAdaptiveDT
dt = 0.001
optimal_iterations = 5
iteration_window = 1
growth_factor = 1.2
[]
steady_state_detection = true
solve_type = PJFNK
nl_rel_tol = 1e-10
nl_abs_tol = 1e-8
nl_max_its = 15
l_tol = 1e-3
l_max_its = 10
[]
[Outputs]
exodus = true
velocity_as_vector = false
show = 'A rho vel p'
[]
(modules/thermal_hydraulics/test/tests/components/junction_one_to_one_1phase/constriction_1phase.i)
# This test is used to test the JunctionOneToOne1Phase1Phase component with unequal areas
# at the junction. The downstream flow channel has an area half that of the
# upstream pipe, so there should be a pressure increase just upstream of the
# junction due to the partial wall. The velocity should increase through the
# junction (approximately by a factor of 2, but there are compressibility effects).
[GlobalParams]
gravity_vector = '0 0 0'
fp = fp
closures = simple_closures
f = 0
initial_T = 300
initial_p = 1e5
initial_vel = 1
[]
[FluidProperties]
[fp]
type = IdealGasFluidProperties
gamma = 1.4
molar_mass = 11.64024372
[]
[]
[Closures]
[simple_closures]
type = Closures1PhaseSimple
[]
[]
[Components]
[left_boundary]
type = InletDensityVelocity1Phase
input = 'left_channel:in'
rho = 466.6666667
vel = 1
[]
[left_channel]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '1 0 0'
length = 0.5
n_elems = 50
A = 1.0
[]
[junction]
type = JunctionOneToOne1Phase
connections = 'left_channel:out right_channel:in'
[]
[right_channel]
type = FlowChannel1Phase
position = '0.5 0 0'
orientation = '1 0 0'
length = 0.5
n_elems = 50
A = 0.5
[]
[right_boundary]
type = Outlet1Phase
input = 'right_channel:out'
p = 1e5
[]
[]
[Preconditioning]
[smp]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
scheme = bdf2
dt = 0.01
num_steps = 10
abort_on_solve_fail = true
solve_type = NEWTON
nl_rel_tol = 1e-10
nl_abs_tol = 1e-8
nl_max_its = 60
l_tol = 1e-4
[]
[Outputs]
exodus = true
show = 'p T vel'
execute_on = 'initial timestep_end'
velocity_as_vector = false
[]
(modules/thermal_hydraulics/test/tests/base/simulation/loop_identification.i)
# This test tests the loop identification function, which creates a map of component
# names to a loop name. "Loops" are defined to be sets of components which are
# physically connected - heat exchanger connections do not constitute physical
# connections in this sense. Note that this test is not meant to actually perform
# any physical computations, so dummy values are provided for the required parameters.
#
# The test configuration for this test is the following:
#
# pipe1 -> corechannel:pipe -> pipe2 -> hx:primary -> pipe1
# j1 j2 j3 j4
#
# inlet -> hx:secondary -> outlet
#
# This test uses the command-line option "--print-component-loops" to print out
# the lists of components in each loop, with the desired output being the
# following:
#
# Loop 1:
#
# corechannel:pipe
# hx:primary
# j1
# j2
# j3
# j4
# pipe1
# pipe2
#
# Loop 2:
#
# hx:secondary
# inlet
# outlet
[GlobalParams]
closures = simple_closures
initial_p = 1e6
initial_T = 300
initial_vel = 0
[]
[FluidProperties]
[fp_liquid]
type = StiffenedGasFluidProperties
gamma = 2.35
q = -1167e3
q_prime = 0
p_inf = 1.e9
cv = 1816
[]
[]
[Closures]
[simple_closures]
type = Closures1PhaseSimple
[]
[]
[SolidProperties]
[hx:wall]
type = ThermalFunctionSolidProperties
k = 1
cp = 1
rho = 1
[]
[]
[Components]
# PRIMARY LOOP
[pipe1]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '1 0 0'
length = 1
n_elems = 1
A = 1
f = 1
fp = fp_liquid
[]
[j1]
type = JunctionOneToOne1Phase
connections = 'pipe1:out corechannel:in'
[]
[corechannel]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '1 0 0'
length = 1
n_elems = 1
A = 1
f = 1
fp = fp_liquid
[]
[j2]
type = JunctionOneToOne1Phase
connections = 'corechannel:out pipe2:in'
[]
[pipe2]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '1 0 0'
length = 1
n_elems = 1
A = 1
f = 1
fp = fp_liquid
[]
[j3]
type = JunctionOneToOne1Phase
connections = 'pipe2:out hx:primary:in'
[]
[hx:primary]
type = FlowChannel1Phase
position = '0 1 0'
orientation = '1 0 0'
length = 1
n_elems = 1
A = 1
f = 1
fp = fp_liquid
[]
[j4]
type = JunctionOneToOne1Phase
connections = 'hx:primary:out pipe1:in'
[]
# HEAT EXCHANGER
[hs]
type = HeatStructurePlate
position = '0 0 0'
orientation = '1 0 0'
length = 1
n_elems = 1
solid_properties = hx:wall
solid_properties_T_ref = '300'
n_part_elems = 1
names = 0
widths = 1
depth = 1
initial_T = 300
[]
[ht_primary]
type = HeatTransferFromHeatStructure1Phase
hs = hs
flow_channel = hx:primary
hs_side = outer
Hw = 0
[]
[ht_secondary]
type = HeatTransferFromHeatStructure1Phase
hs = hs
flow_channel = hx:secondary
hs_side = inner
Hw = 0
[]
# SECONDARY LOOP
[inlet]
type = SolidWall1Phase
input = 'hx:secondary:out'
[]
[hx:secondary]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '1 0 0'
length = 1
n_elems = 1
A = 1
f = 1
fp = fp_liquid
[]
[outlet]
type = SolidWall1Phase
input = 'hx:secondary:in'
[]
[]
[Problem]
solve = false
[]
[Executioner]
type = Transient
num_steps = 1
[]
[Outputs]
[console]
type = Console
system_info = ''
enable = false
[]
[]
(modules/thermal_hydraulics/test/tests/problems/natural_circulation/junction_one_to_one.i)
# This version uses JunctionOneToOne
!include base_params.i
!include base.i
[Components]
[junction_heated_top]
type = JunctionOneToOne1Phase
connections = 'heated_pipe:out top_pipe:in'
[]
[junction_top_cooled]
type = JunctionOneToOne1Phase
connections = 'top_pipe:out cooled_pipe:in'
[]
[junction_cooled_bottom]
type = JunctionOneToOne1Phase
connections = 'cooled_pipe:out bottom_pipe:in'
[]
[junction_bottom_heated]
type = JunctionOneToOne1Phase
connections = 'bottom_pipe:out heated_pipe:in'
[]
[]
(modules/thermal_hydraulics/test/tests/problems/brayton_cycle/recuperated_brayton_cycle.i)
# This input file models an open, recuperated Brayton cycle with a PID
# controlled start up using a coupled motor.
#
# Heat is supplied to the system by a volumetric heat source, and a second heat
# source is used to model a recuperator. The recuperator transfers heat from the
# turbine exhaust gas to the compressor outlet gas.
#
# Initially the fluid and heat structures are at rest at ambient conditions,
# and the shaft speed is zero.
# The transient is controlled as follows:
# * 0 - 2000 s: Motor increases shaft speed to approx. 85,000 RPM by PID control
# * 1000 - 8600 s: Power in main heat source increases from 0 - 104 kW
# * 2000 - 200000 s: Torque supplied by turbine increases to steady state level
# as working fluid temperature increases. Torque supplied by
# the motor is ramped down to 0 N-m transitioning shaft control
# to the turbine at its rated speed of 96,000 RPM.
I_motor = 1.0
I_generator = 1.0
generator_torque_per_shaft_speed = -0.00025
motor_ramp_up_duration = 3605
motor_ramp_down_duration = 1800
post_motor_time = 2160000
t1 = ${motor_ramp_up_duration}
t2 = ${fparse t1 + motor_ramp_down_duration}
t3 = ${fparse t2 + post_motor_time}
D1 = 0.15
D2 = ${D1}
D3 = ${D1}
D4 = ${D1}
D5 = ${D1}
D6 = ${D1}
D7 = ${D1}
D8 = ${D1}
A1 = ${fparse 0.25 * pi * D1^2}
A2 = ${fparse 0.25 * pi * D2^2}
A3 = ${fparse 0.25 * pi * D3^2}
A4 = ${fparse 0.25 * pi * D4^2}
A5 = ${fparse 0.25 * pi * D5^2}
A6 = ${fparse 0.25 * pi * D6^2}
A7 = ${fparse 0.25 * pi * D7^2}
A8 = ${fparse 0.25 * pi * D8^2}
recuperator_width = 0.15
L1 = 5.0
L2 = ${L1}
L3 = ${fparse 2 * L1}
L4 = ${fparse 2 * L1}
L5 = ${L1}
L6 = ${L1}
L7 = ${fparse L1 + recuperator_width}
L8 = ${L1}
x1 = 0.0
x2 = ${fparse x1 + L1}
x3 = ${fparse x2 + L2}
x4 = ${x3}
x5 = ${fparse x4 - L4}
x6 = ${x5}
x7 = ${fparse x6 + L6}
x8 = ${fparse x7 + L7}
y1 = 0
y2 = ${y1}
y3 = ${y2}
y4 = ${fparse y3 - L3}
y5 = ${y4}
y6 = ${fparse y5 + L5}
y7 = ${y6}
y8 = ${y7}
x1_out = ${fparse x1 + L1 - 0.001}
x2_in = ${fparse x2 + 0.001}
y5_in = ${fparse y5 + 0.001}
x6_out = ${fparse x6 + L6 - 0.001}
x7_in = ${fparse x7 + 0.001}
y8_in = ${fparse y8 + 0.001}
y8_out = ${fparse y8 + L8 - 0.001}
hot_leg_in = ${y8_in}
hot_leg_out = ${y8_out}
cold_leg_in = ${fparse y3 - 0.001}
cold_leg_out = ${fparse y3 - (L3/2) - 0.001}
n_elems1 = 5
n_elems2 = ${n_elems1}
n_elems3 = ${fparse 2 * n_elems1}
n_elems4 = ${fparse 2 * n_elems1}
n_elems5 = ${n_elems1}
n_elems6 = ${n_elems1}
n_elems7 = ${n_elems1}
n_elems8 = ${n_elems1}
A_ref_comp = ${fparse 0.5 * (A1 + A2)}
V_comp = ${fparse A_ref_comp * 1.0}
I_comp = 1.0
A_ref_turb = ${fparse 0.5 * (A4 + A5)}
V_turb = ${fparse A_ref_turb * 1.0}
I_turb = 1.0
c0_rated_comp = 351.6925137
rho0_rated_comp = 1.146881112
rated_mfr = 0.25
speed_rated_rpm = 96000
speed_rated = ${fparse speed_rated_rpm * 2 * pi / 60.0}
speed_initial = 0
eff_comp = 0.79
eff_turb = 0.843
T_ambient = 300
p_ambient = 1e5
hs_power = 105750
[GlobalParams]
gravity_vector = '0 0 0'
initial_p = ${p_ambient}
initial_T = ${T_ambient}
initial_vel = 0
initial_vel_x = 0
initial_vel_y = 0
initial_vel_z = 0
fp = fp_air
closures = closures
f = 0
scaling_factor_1phase = '1 1 1e-5'
scaling_factor_rhoV = 1
scaling_factor_rhouV = 1e-2
scaling_factor_rhovV = 1e-2
scaling_factor_rhowV = 1e-2
scaling_factor_rhoEV = 1e-5
scaling_factor_temperature = 1e-2
rdg_slope_reconstruction = none
[]
[FluidProperties]
[fp_air]
type = IdealGasFluidProperties
emit_on_nan = none
[]
[]
[SolidProperties]
[steel]
type = ThermalFunctionSolidProperties
rho = 8050
k = 45
cp = 466
[]
[]
[Closures]
[closures]
type = Closures1PhaseSimple
[]
[]
[Functions]
##########################
# Motor
##########################
# Functions for control logic that determines when to shut off the PID system
[is_tripped_fn]
type = ParsedFunction
symbol_names = 'motor_torque turbine_torque'
symbol_values = 'motor_torque turbine_torque'
expression = 'turbine_torque > motor_torque'
[]
[PID_tripped_constant_value]
type = ConstantFunction
value = 1
[]
[PID_tripped_status_fn]
type = ParsedFunction
symbol_values = 'PID_trip_status'
symbol_names = 'PID_trip_status'
expression = 'PID_trip_status'
[]
[time_fn]
type = ParsedFunction
expression = t
[]
# Shutdown function which ramps down the motor once told by the control logic
[motor_torque_fn_shutdown]
type = ParsedFunction
symbol_values = 'PID_trip_status time_trip'
symbol_names = 'PID_trip_status time_trip'
expression = 'if(PID_trip_status = 1, max(2.4 - (2.4 * ((t - time_trip) / 35000)),0.0), 1)'
[]
# Generates motor power curve
[motor_power_fn]
type = ParsedFunction
expression = 'torque * speed'
symbol_names = 'torque speed'
symbol_values = 'motor_torque shaft:omega'
[]
##########################
# Generator
##########################
# Generates generator torque curve
[generator_torque_fn]
type = ParsedFunction
expression = 'slope * t'
symbol_names = 'slope'
symbol_values = '${generator_torque_per_shaft_speed}'
[]
# Generates generator power curve
[generator_power_fn]
type = ParsedFunction
expression = 'torque * speed'
symbol_names = 'torque speed'
symbol_values = 'generator_torque shaft:omega'
[]
##########################
# Reactor
##########################
# Ramps up reactor power when activated by control logic
[power_fn]
type = PiecewiseLinear
x = '0 1000 8600'
y = '0 0 ${hs_power}'
[]
##########################
# Compressor
##########################
# compressor pressure ratios
[rp_comp1]
type = PiecewiseLinear
data_file = 'rp_comp1.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp2]
type = PiecewiseLinear
data_file = 'rp_comp2.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp3]
type = PiecewiseLinear
data_file = 'rp_comp3.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp4]
type = PiecewiseLinear
data_file = 'rp_comp4.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_comp5]
type = PiecewiseLinear
data_file = 'rp_comp5.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
# compressor efficiencies
[eff_comp1]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp2]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp3]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp4]
type = ConstantFunction
value = ${eff_comp}
[]
[eff_comp5]
type = ConstantFunction
value = ${eff_comp}
[]
##########################
# Turbine
##########################
# turbine pressure ratios
[rp_turb0]
type = ConstantFunction
value = 1
[]
[rp_turb1]
type = PiecewiseLinear
data_file = 'rp_turb1.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb2]
type = PiecewiseLinear
data_file = 'rp_turb2.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb3]
type = PiecewiseLinear
data_file = 'rp_turb3.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb4]
type = PiecewiseLinear
data_file = 'rp_turb4.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
[rp_turb5]
type = PiecewiseLinear
data_file = 'rp_turb5.csv'
x_index_in_file = 0
y_index_in_file = 1
format = columns
extrap = true
[]
# turbine efficiency
[eff_turb1]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb2]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb3]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb4]
type = ConstantFunction
value = ${eff_turb}
[]
[eff_turb5]
type = ConstantFunction
value = ${eff_turb}
[]
[]
[Components]
# system inlet pulling air from the open atmosphere
[inlet]
type = InletStagnationPressureTemperature1Phase
input = 'pipe1:in'
p0 = ${p_ambient}
T0 = ${T_ambient}
[]
# Inlet pipe
[pipe1]
type = FlowChannel1Phase
position = '${x1} ${y1} 0'
orientation = '1 0 0'
length = ${L1}
n_elems = ${n_elems1}
A = ${A1}
[]
# Compressor as defined in MAGNET PCU document (Guillen 2020)
[compressor]
type = ShaftConnectedCompressor1Phase
position = '${x2} ${y2} 0'
inlet = 'pipe1:out'
outlet = 'pipe2:in'
A_ref = ${A_ref_comp}
volume = ${V_comp}
omega_rated = ${speed_rated}
mdot_rated = ${rated_mfr}
c0_rated = ${c0_rated_comp}
rho0_rated = ${rho0_rated_comp}
# Determines which compression ratio curve and efficiency curve to use depending on ratio of speed/rated_speed
speeds = '0.5208 0.6250 0.7292 0.8333 0.9375'
Rp_functions = 'rp_comp1 rp_comp2 rp_comp3 rp_comp4 rp_comp5'
eff_functions = 'eff_comp1 eff_comp2 eff_comp3 eff_comp4 eff_comp5'
min_pressure_ratio = 1.0
speed_cr_I = 0
inertia_const = ${I_comp}
inertia_coeff = '${I_comp} 0 0 0'
# assume no shaft friction
speed_cr_fr = 0
tau_fr_const = 0
tau_fr_coeff = '0 0 0 0'
use_scalar_variables = false
[]
# Outlet pipe from the compressor
[pipe2]
type = FlowChannel1Phase
position = '${x2} ${y2} 0'
orientation = '1 0 0'
length = ${L2}
n_elems = ${n_elems2}
A = ${A2}
[]
# 90 degree connection between pipe 2 and 3
[junction2_cold_leg]
type = VolumeJunction1Phase
connections = 'pipe2:out cold_leg:in'
position = '${x3} ${y3} 0'
volume = ${fparse A2*0.1}
use_scalar_variables = false
[]
# Cold leg of the recuperator
[cold_leg]
type = FlowChannel1Phase
position = '${x3} ${y3} 0'
orientation = '0 -1 0'
length = ${fparse L3/2}
n_elems = ${fparse n_elems3/2}
A = ${A3}
[]
# Recuperator which transfers heat from exhaust gas to reactor inlet gas to improve thermal efficency
[recuperator]
type = HeatStructureCylindrical
orientation = '0 -1 0'
position = '${x3} ${y3} 0'
length = ${fparse L3/2}
widths = ${recuperator_width}
n_elems = ${fparse n_elems3/2}
n_part_elems = 2
names = recuperator
solid_properties = steel
solid_properties_T_ref = '300'
inner_radius = ${D1}
[]
# heat transfer from recuperator to cold leg
[heat_transfer_cold_leg]
type = HeatTransferFromHeatStructure1Phase
flow_channel = cold_leg
hs = recuperator
hs_side = OUTER
Hw = 10000
[]
# heat transfer from hot leg to recuperator
[heat_transfer_hot_leg]
type = HeatTransferFromHeatStructure1Phase
flow_channel = hot_leg
hs = recuperator
hs_side = INNER
Hw = 10000
[]
[junction_cold_leg_3]
type = JunctionOneToOne1Phase
connections = 'cold_leg:out pipe3:in'
[]
[pipe3]
type = FlowChannel1Phase
position = '${x3} ${fparse y3 - (L3/2)} 0'
orientation = '0 -1 0'
length = ${fparse L3/2}
n_elems = ${fparse n_elems3/2}
A = ${A3}
[]
# 90 degree connection between pipe 3 and 4
[junction3_4]
type = VolumeJunction1Phase
connections = 'pipe3:out pipe4:in'
position = '${x4} ${y4} 0'
volume = ${fparse A3*0.1}
use_scalar_variables = false
[]
# Pipe through the "reactor core"
[pipe4]
type = FlowChannel1Phase
position = '${x4} ${y4} 0'
orientation = '-1 0 0'
length = ${L4}
n_elems = ${n_elems4}
A = ${A4}
[]
# "Reactor Core" and it's associated heat transfer to pipe 4
[reactor]
type = HeatStructureCylindrical
orientation = '-1 0 0'
position = '${x4} ${y4} 0'
length = ${L4}
widths = 0.15
n_elems = ${n_elems4}
n_part_elems = 2
names = core
solid_properties = steel
solid_properties_T_ref = '300'
[]
[total_power]
type = TotalPower
power = 0
[]
[heat_generation]
type = HeatSourceFromTotalPower
power = total_power
hs = reactor
regions = core
[]
[heat_transfer]
type = HeatTransferFromHeatStructure1Phase
flow_channel = pipe4
hs = reactor
hs_side = OUTER
Hw = 10000
[]
# 90 degree connection between pipe 4 and 5
[junction4_5]
type = VolumeJunction1Phase
connections = 'pipe4:out pipe5:in'
position = '${x5} ${y5} 0'
volume = ${fparse A4*0.1}
use_scalar_variables = false
[]
# Pipe carrying hot gas back to the PCU
[pipe5]
type = FlowChannel1Phase
position = '${x5} ${y5} 0'
orientation = '0 1 0'
length = ${L5}
n_elems = ${n_elems5}
A = ${A5}
[]
# 90 degree connection between pipe 5 and 6
[junction5_6]
type = VolumeJunction1Phase
connections = 'pipe5:out pipe6:in'
position = '${x6} ${y6} 0'
volume = ${fparse A5*0.1}
use_scalar_variables = false
[]
# Inlet pipe to the turbine
[pipe6]
type = FlowChannel1Phase
position = '${x6} ${y6} 0'
orientation = '1 0 0'
length = ${L6}
n_elems = ${n_elems6}
A = ${A6}
[]
# Turbine as defined in MAGNET PCU document (Guillen 2020) and (Wright 2006)
[turbine]
type = ShaftConnectedCompressor1Phase
position = '${x7} ${y7} 0'
inlet = 'pipe6:out'
outlet = 'pipe7:in'
A_ref = ${A_ref_turb}
volume = ${V_turb}
# A turbine is treated as an "inverse" compressor, this value determines if component is to be treated as turbine or compressor
# If treat_as_turbine is omitted, code automatically assumes it is a compressor
treat_as_turbine = true
omega_rated = ${speed_rated}
mdot_rated = ${rated_mfr}
c0_rated = ${c0_rated_comp}
rho0_rated = ${rho0_rated_comp}
# Determines which compression ratio curve and efficiency curve to use depending on ratio of speed/rated_speed
speeds = '0 0.5208 0.6250 0.7292 0.8333 0.9375'
Rp_functions = 'rp_turb0 rp_turb1 rp_turb2 rp_turb3 rp_turb4 rp_turb5'
eff_functions = 'eff_turb1 eff_turb1 eff_turb2 eff_turb3 eff_turb4 eff_turb5'
min_pressure_ratio = 1.0
speed_cr_I = 0
inertia_const = ${I_turb}
inertia_coeff = '${I_turb} 0 0 0'
# assume no shaft friction
speed_cr_fr = 0
tau_fr_const = 0
tau_fr_coeff = '0 0 0 0'
use_scalar_variables = false
[]
# Outlet pipe from turbine
[pipe7]
type = FlowChannel1Phase
position = '${x7} ${y7} 0'
orientation = '1 0 0'
length = ${L7}
n_elems = ${n_elems7}
A = ${A7}
[]
# 90 degree connection between pipe 7 and 8
[junction7_hot_leg]
type = VolumeJunction1Phase
connections = 'pipe7:out hot_leg:in'
position = '${x8} ${y8} 0'
volume = ${fparse A7*0.1}
use_scalar_variables = false
[]
# Hot leg of the recuperator
[hot_leg]
type = FlowChannel1Phase
position = '${x8} ${y8} 0'
orientation = '0 1 0'
length = ${L8}
n_elems = ${n_elems8}
A = ${A8}
[]
# System outlet dumping exhaust gas to the atmosphere
[outlet]
type = Outlet1Phase
input = 'hot_leg:out'
p = ${p_ambient}
[]
# Roatating shaft connecting motor, compressor, turbine, and generator
[shaft]
type = Shaft
connected_components = 'motor compressor turbine generator'
initial_speed = ${speed_initial}
[]
# 3-Phase electircal motor used for system start-up, controlled by PID
[motor]
type = ShaftConnectedMotor
inertia = ${I_motor}
torque = 0 # controlled
[]
# Electric generator supplying power to the grid
[generator]
type = ShaftConnectedMotor
inertia = ${I_generator}
torque = generator_torque_fn
[]
[]
# Control logics which govern startup of the motor, startup of the "reactor core", and shutdown of the motor
[ControlLogic]
# Sets desired shaft speed to be reached by motor NOTE: SHOULD BE SET LOWER THAN RATED TURBINE RPM
[set_point]
type = GetFunctionValueControl
function = ${fparse speed_rated_rpm - 9000}
[]
# PID with gains determined by iterative process NOTE: Gain values are system specific
[initial_motor_PID]
type = PIDControl
set_point = set_point:value
input = shaft_RPM
initial_value = 0
K_p = 0.0011
K_i = 0.00000004
K_d = 0
[]
# Determines when the PID system should be running and when it should begin the shutdown cycle. If needed: PID output, else: shutdown function
[logic]
type = ParsedFunctionControl
function = 'if(motor+0.5 > turb, PID, shutdown_fn)'
symbol_names = 'motor turb PID shutdown_fn'
symbol_values = 'motor_torque turbine_torque initial_motor_PID:output motor_torque_fn_shutdown'
[]
# Takes the output generated in [logic] and applies it to the motor torque
[motor_PID]
type = SetComponentRealValueControl
component = motor
parameter = torque
value = logic:value
[]
# Determines when to turn on heat source
[power_logic]
type = ParsedFunctionControl
function = 'power_fn'
symbol_names = 'power_fn'
symbol_values = 'power_fn'
[]
# Applies heat source to the total_power block
[power_applied]
type = SetComponentRealValueControl
component = total_power
parameter = power
value = power_logic:value
[]
[]
[Controls]
# Enables set_PID_tripped
[PID_trip_status]
type = ConditionalFunctionEnableControl
conditional_function = is_tripped_fn
enable_objects = 'AuxScalarKernels::PID_trip_status_aux'
execute_on = 'TIMESTEP_END'
[]
# Enables set_time_PID
[time_PID]
type = ConditionalFunctionEnableControl
conditional_function = PID_tripped_status_fn
disable_objects = 'AuxScalarKernels::time_trip_aux'
execute_on = 'TIMESTEP_END'
[]
[]
[AuxVariables]
# Creates a variable that will later be set to the time when tau_turbine > tau_motor
[time_trip]
order = FIRST
family = SCALAR
[]
# Creates variable which indicates if tau_turbine > tau_motor....... If tau_motor > tau_turbine, 0, else 1
[PID_trip_status]
order = FIRST
family = SCALAR
initial_condition = 0
[]
[]
[AuxScalarKernels]
# Creates variable from time_fn which indicates when tau_turbine > tau_motor
[time_trip_aux]
type = FunctionScalarAux
function = time_fn
variable = time_trip
execute_on = 'TIMESTEP_END'
[]
# Overwrites variable PID_trip_status to the value from PID_tripped_constant_value (changes 0 to 1)
[PID_trip_status_aux]
type = FunctionScalarAux
function = PID_tripped_constant_value
variable = PID_trip_status
execute_on = 'TIMESTEP_END'
enable = false
[]
[]
[Postprocessors]
# Indicates when tau_turbine > tau_motor
[trip_time]
type = ScalarVariable
variable = time_trip
execute_on = 'TIMESTEP_END'
[]
##########################
# Motor
##########################
[motor_torque]
type = RealComponentParameterValuePostprocessor
component = motor
parameter = torque
execute_on = 'INITIAL TIMESTEP_END'
[]
[motor_power]
type = FunctionValuePostprocessor
function = motor_power_fn
execute_on = 'INITIAL TIMESTEP_END'
[]
##########################
# generator
##########################
[generator_torque]
type = ShaftConnectedComponentPostprocessor
quantity = torque
shaft_connected_component_uo = generator:shaftconnected_uo
execute_on = 'INITIAL TIMESTEP_END'
[]
[generator_power]
type = FunctionValuePostprocessor
function = generator_power_fn
execute_on = 'INITIAL TIMESTEP_END'
[]
##########################
# Shaft
##########################
# Speed in rad/s
[shaft_speed]
type = ScalarVariable
variable = 'shaft:omega'
execute_on = 'INITIAL TIMESTEP_END'
[]
# speed in RPM
[shaft_RPM]
type = ParsedPostprocessor
pp_names = 'shaft_speed'
expression = '(shaft_speed * 60) /( 2 * ${fparse pi})'
execute_on = 'INITIAL TIMESTEP_END'
[]
##########################
# Compressor
##########################
[comp_dissipation_torque]
type = ElementAverageValue
variable = dissipation_torque
block = 'compressor'
execute_on = 'INITIAL TIMESTEP_END'
[]
[comp_isentropic_torque]
type = ElementAverageValue
variable = isentropic_torque
block = 'compressor'
execute_on = 'INITIAL TIMESTEP_END'
[]
[comp_friction_torque]
type = ElementAverageValue
variable = friction_torque
block = 'compressor'
execute_on = 'INITIAL TIMESTEP_END'
[]
[compressor_torque]
type = ParsedPostprocessor
pp_names = 'comp_dissipation_torque comp_isentropic_torque comp_friction_torque'
expression = 'comp_dissipation_torque + comp_isentropic_torque + comp_friction_torque'
[]
[p_in_comp]
type = PointValue
variable = p
point = '${x1_out} ${y1} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_out_comp]
type = PointValue
variable = p
point = '${x2_in} ${y2} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_ratio_comp]
type = ParsedPostprocessor
pp_names = 'p_in_comp p_out_comp'
expression = 'p_out_comp / p_in_comp'
execute_on = 'INITIAL TIMESTEP_END'
[]
[T_in_comp]
type = PointValue
variable = T
point = '${x1_out} ${y1} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[T_out_comp]
type = PointValue
variable = T
point = '${x2_in} ${y2} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[T_ratio_comp]
type = ParsedPostprocessor
pp_names = 'T_in_comp T_out_comp'
expression = '(T_out_comp - T_in_comp) / T_out_comp'
execute_on = 'INITIAL TIMESTEP_END'
[]
[mfr_comp]
type = ADFlowJunctionFlux1Phase
boundary = pipe1:out
connection_index = 0
equation = mass
junction = compressor
[]
##########################
# turbine
##########################
[turb_dissipation_torque]
type = ElementAverageValue
variable = dissipation_torque
block = 'turbine'
execute_on = 'INITIAL TIMESTEP_END'
[]
[turb_isentropic_torque]
type = ElementAverageValue
variable = isentropic_torque
block = 'turbine'
execute_on = 'INITIAL TIMESTEP_END'
[]
[turb_friction_torque]
type = ElementAverageValue
variable = friction_torque
block = 'turbine'
execute_on = 'INITIAL TIMESTEP_END'
[]
[turbine_torque]
type = ParsedPostprocessor
pp_names = 'turb_dissipation_torque turb_isentropic_torque turb_friction_torque'
expression = 'turb_dissipation_torque + turb_isentropic_torque + turb_friction_torque'
[]
[p_in_turb]
type = PointValue
variable = p
point = '${x6_out} ${y6} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_out_turb]
type = PointValue
variable = p
point = '${x7_in} ${y7} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[p_ratio_turb]
type = ParsedPostprocessor
pp_names = 'p_in_turb p_out_turb'
expression = 'p_in_turb / p_out_turb'
execute_on = 'INITIAL TIMESTEP_END'
[]
[T_in_turb]
type = PointValue
variable = T
point = '${x6_out} ${y6} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[T_out_turb]
type = PointValue
variable = T
point = '${x7_in} ${y7} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[mfr_turb]
type = ADFlowJunctionFlux1Phase
boundary = pipe6:out
connection_index = 0
equation = mass
junction = turbine
[]
##########################
# Recuperator
##########################
[cold_leg_in]
type = PointValue
variable = T
point = '${x3} ${cold_leg_in} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[cold_leg_out]
type = PointValue
variable = T
point = '${x3} ${cold_leg_out} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[hot_leg_in]
type = PointValue
variable = T
point = '${x8} ${hot_leg_in} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[hot_leg_out]
type = PointValue
variable = T
point = '${x8} ${hot_leg_out} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
##########################
# Reactor
##########################
[reactor_inlet]
type = PointValue
variable = T
point = '${x4} ${y4} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[reactor_outlet]
type = PointValue
variable = T
point = '${x5} ${y5_in} 0'
execute_on = 'INITIAL TIMESTEP_END'
[]
[]
[Executioner]
type = Transient
scheme = 'bdf2'
end_time = ${t3}
[TimeStepper]
type = IterationAdaptiveDT
dt = 0.01
growth_factor = 1.1
cutback_factor = 0.9
[]
dtmin = 1e-5
dtmax = 1000
steady_state_detection = true
steady_state_start_time = 200000
solve_type = NEWTON
nl_rel_tol = 1e-8
nl_abs_tol = 1e-8
nl_max_its = 15
l_tol = 1e-4
l_max_its = 10
petsc_options_iname = '-pc_type'
petsc_options_value = ' lu '
[]
[Outputs]
[e]
type = Exodus
file_base = 'recuperated_brayton_cycle_out'
[]
[csv]
type = CSV
file_base = 'recuperated_brayton_cycle'
execute_vector_postprocessors_on = 'INITIAL'
[]
[console]
type = Console
show = 'shaft_speed p_ratio_comp p_ratio_turb pressure_ratio pressure_ratio'
[]
[]
(modules/thermal_hydraulics/tutorials/single_phase_flow/05_secondary_side.i)
T_in = 300. # K
m_dot_in = 1e-2 # kg/s
press = 10e5 # Pa
# core parameters
core_length = 1. # m
core_n_elems = 25
core_dia = '${units 2. cm -> m}'
core_pitch = '${units 8.7 cm -> m}'
A_core = '${fparse core_pitch^2 - 0.25 *pi * core_dia^2}'
P_wet_core = '${fparse 4*core_pitch + pi * core_dia}'
Dh_core = '${fparse 4 * A_core / P_wet_core}'
# pipe parameters
pipe_dia = '${units 10. cm -> m}'
A_pipe = '${fparse 0.25 * pi * pipe_dia^2}'
tot_power = 2000 # W
# heat exchanger parameters
hx_dia_inner = '${units 12. cm -> m}'
hx_wall_thickness = '${units 5. mm -> m}'
hx_dia_outer = '${units 50. cm -> m}'
hx_radius_wall = '${fparse hx_dia_inner / 2. + hx_wall_thickness}'
hx_length = 1.5 # m
hx_n_elems = 25
m_dot_sec_in = 1. # kg/s
[GlobalParams]
initial_p = ${press}
initial_vel = 0.0001
initial_T = ${T_in}
initial_vel_x = 0
initial_vel_y = 0
initial_vel_z = 0
gravity_vector = '0 0 0'
rdg_slope_reconstruction = minmod
scaling_factor_1phase = '1 1e-2 1e-4'
scaling_factor_rhoV = 1
scaling_factor_rhouV = 1e-2
scaling_factor_rhovV = 1e-2
scaling_factor_rhowV = 1e-2
scaling_factor_rhoEV = 1e-4
closures = thm_closures
fp = he
[]
[Functions]
[m_dot_sec_fn]
type = PiecewiseLinear
xy_data = '
0 0
10 ${m_dot_sec_in}'
[]
[]
[FluidProperties]
[he]
type = IdealGasFluidProperties
molar_mass = 4e-3
gamma = 1.67
k = 0.2556
mu = 3.22639e-5
[]
[water]
type = StiffenedGasFluidProperties
gamma = 2.35
cv = 1816.0
q = -1.167e6
p_inf = 1.0e9
q_prime = 0
[]
[]
[Closures]
[thm_closures]
type = Closures1PhaseTHM
[]
[]
[SolidProperties]
[steel]
type = ThermalFunctionSolidProperties
rho = 8050
k = 45
cp = 466
[]
[]
[Components]
[total_power]
type = TotalPower
power = ${tot_power}
[]
[up_pipe_1]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '0 0 1'
length = 0.5
n_elems = 15
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct1]
type = JunctionParallelChannels1Phase
position = '0 0 0.5'
connections = 'up_pipe_1:out core_chan:in'
volume = 1e-5
use_scalar_variables = false
[]
[core_chan]
type = FlowChannel1Phase
position = '0 0 0.5'
orientation = '0 0 1'
length = ${core_length}
n_elems = ${core_n_elems}
roughness = .0001
A = ${A_core}
D_h = ${Dh_core}
[]
[core_hs]
type = HeatStructureCylindrical
position = '0 0 0.5'
orientation = '0 0 1'
length = ${core_length}
n_elems = ${core_n_elems}
names = 'block'
widths = '${fparse core_dia / 2.}'
solid_properties = 'steel'
solid_properties_T_ref = '300'
n_part_elems = 3
[]
[core_heating]
type = HeatSourceFromTotalPower
hs = core_hs
regions = block
power = total_power
[]
[core_ht]
type = HeatTransferFromHeatStructure1Phase
flow_channel = core_chan
hs = core_hs
hs_side = outer
P_hf = '${fparse pi * core_dia}'
[]
[jct2]
type = JunctionParallelChannels1Phase
position = '0 0 1.5'
connections = 'core_chan:out up_pipe_2:in'
volume = 1e-5
use_scalar_variables = false
[]
[up_pipe_2]
type = FlowChannel1Phase
position = '0 0 1.5'
orientation = '0 0 1'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct3]
type = JunctionOneToOne1Phase
connections = 'up_pipe_2:out top_pipe_1:in'
[]
[top_pipe_1]
type = FlowChannel1Phase
position = '0 0 2'
orientation = '1 0 0'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[top_pipe_2]
type = FlowChannel1Phase
position = '0.5 0 2'
orientation = '1 0 0'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct4]
type = VolumeJunction1Phase
position = '0.5 0 2'
volume = 1e-5
connections = 'top_pipe_1:out top_pipe_2:in press_pipe:in'
use_scalar_variables = false
[]
[press_pipe]
type = FlowChannel1Phase
position = '0.5 0 2'
orientation = '0 1 0'
length = 0.2
n_elems = 5
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[pressurizer]
type = InletStagnationPressureTemperature1Phase
p0 = ${press}
T0 = ${T_in}
input = press_pipe:out
[]
[jct5]
type = JunctionOneToOne1Phase
connections = 'top_pipe_2:out down_pipe_1:in'
[]
[down_pipe_1]
type = FlowChannel1Phase
position = '1 0 2'
orientation = '0 0 -1'
length = 0.25
A = ${A_pipe}
n_elems = 5
[]
[jct6]
type = JunctionParallelChannels1Phase
position = '1 0 1.75'
connections = 'down_pipe_1:out hx/pri:in'
volume = 1e-5
use_scalar_variables = false
[]
[hx]
[pri]
type = FlowChannel1Phase
position = '1 0 1.75'
orientation = '0 0 -1'
length = ${hx_length}
n_elems = ${hx_n_elems}
roughness = 1e-5
A = '${fparse pi * hx_dia_inner * hx_dia_inner / 4.}'
D_h = ${hx_dia_inner}
[]
[ht_pri]
type = HeatTransferFromHeatStructure1Phase
hs = hx/wall
hs_side = inner
flow_channel = hx/pri
P_hf = '${fparse pi * hx_dia_inner}'
[]
[wall]
type = HeatStructureCylindrical
position = '1 0 1.75'
orientation = '0 0 -1'
length = ${hx_length}
n_elems = ${hx_n_elems}
widths = '${hx_wall_thickness}'
n_part_elems = '3'
solid_properties = 'steel'
solid_properties_T_ref = '300'
names = '0'
inner_radius = '${fparse hx_dia_inner / 2.}'
[]
[ht_sec]
type = HeatTransferFromHeatStructure1Phase
hs = hx/wall
hs_side = outer
flow_channel = hx/sec
P_hf = '${fparse 2 * pi * hx_radius_wall}'
[]
[sec]
type = FlowChannel1Phase
position = '${fparse 1 + hx_wall_thickness} 0 0.25'
orientation = '0 0 1'
length = ${hx_length}
n_elems = ${hx_n_elems}
A = '${fparse pi * (hx_dia_outer * hx_dia_outer / 4. - hx_radius_wall * hx_radius_wall)}'
D_h = '${fparse hx_dia_outer - (2 * hx_radius_wall)}'
fp = water
initial_T = 300
[]
[]
[jct7]
type = JunctionParallelChannels1Phase
position = '1 0 0.5'
connections = 'hx/pri:out down_pipe_2:in'
volume = 1e-5
use_scalar_variables = false
[]
[down_pipe_2]
type = FlowChannel1Phase
position = '1 0 0.25'
orientation = '0 0 -1'
length = 0.25
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct8]
type = JunctionOneToOne1Phase
connections = 'down_pipe_2:out bottom_1:in'
[]
[bottom_1]
type = FlowChannel1Phase
position = '1 0 0'
orientation = '-1 0 0'
length = 0.5
n_elems = 5
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[pump]
type = Pump1Phase
position = '0.5 0 0'
connections = 'bottom_1:out bottom_2:in'
volume = 1e-4
A_ref = ${A_pipe}
head = 0
use_scalar_variables = false
[]
[bottom_2]
type = FlowChannel1Phase
position = '0.5 0 0'
orientation = '-1 0 0'
length = 0.5
n_elems = 5
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct9]
type = JunctionOneToOne1Phase
connections = 'bottom_2:out up_pipe_1:in'
[]
[inlet_sec]
type = InletMassFlowRateTemperature1Phase
input = 'hx/sec:in'
m_dot = 0
T = 300
[]
[outlet_sec]
type = Outlet1Phase
input = 'hx/sec:out'
p = 1e5
[]
[]
[ControlLogic]
[set_point]
type = GetFunctionValueControl
function = ${m_dot_in}
[]
[pid]
type = PIDControl
initial_value = 0.0
set_point = set_point:value
input = m_dot_pump
K_p = 1.
K_i = 4.
K_d = 0
[]
[set_pump_head]
type = SetComponentRealValueControl
component = pump
parameter = head
value = pid:output
[]
[m_dot_sec_inlet_ctrl]
type = GetFunctionValueControl
function = m_dot_sec_fn
[]
[set_m_dot_sec_ctrl]
type = SetComponentRealValueControl
component = inlet_sec
parameter = m_dot
value = m_dot_sec_inlet_ctrl:value
[]
[]
[Postprocessors]
[power_to_coolant]
type = ADHeatRateConvection1Phase
block = core_chan
P_hf = '${fparse pi *core_dia}'
[]
[m_dot_pump]
type = ADFlowJunctionFlux1Phase
boundary = core_chan:in
connection_index = 1
equation = mass
junction = jct7
[]
[core_T_out]
type = SideAverageValue
boundary = core_chan:out
variable = T
[]
[core_p_in]
type = SideAverageValue
boundary = core_chan:in
variable = p
[]
[core_p_out]
type = SideAverageValue
boundary = core_chan:out
variable = p
[]
[core_delta_p]
type = ParsedPostprocessor
pp_names = 'core_p_in core_p_out'
expression = 'core_p_in - core_p_out'
[]
[hx_pri_T_out]
type = SideAverageValue
boundary = hx/pri:out
variable = T
[]
[hx_sec_T_in]
type = SideAverageValue
boundary = inlet_sec
variable = T
[]
[hx_sec_T_out]
type = SideAverageValue
boundary = outlet_sec
variable = T
[]
[m_dot_sec]
type = ADFlowBoundaryFlux1Phase
boundary = inlet_sec
equation = mass
[]
[]
[Preconditioning]
[pc]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
start_time = 0
[TimeStepper]
type = IterationAdaptiveDT
dt = 1
[]
dtmax = 5
end_time = 500
line_search = basic
solve_type = NEWTON
petsc_options_iname = '-pc_type'
petsc_options_value = 'lu'
nl_rel_tol = 0
nl_abs_tol = 1e-8
nl_max_its = 25
[]
[Outputs]
exodus = true
[console]
type = Console
max_rows = 1
outlier_variable_norms = false
[]
print_linear_residuals = false
[]
(modules/thermal_hydraulics/test/tests/problems/pressure_drop/pressure_drop_with_junction.i)
nelem = 50
friction_factor = 1e4
area = 0.176752
mfr_final = 1.0
p_out = 7e6
T_in = 300
ramp_time = 5.0
[GlobalParams]
gravity_vector = '0 0 0'
initial_T = ${T_in}
initial_p = ${p_out}
initial_vel = 0
closures = closures
rdg_slope_reconstruction = full
scaling_factor_1phase = '1 1 1e-5'
[]
[FluidProperties]
[h2]
type = IdealGasFluidProperties
gamma = 1.3066
molar_mass = 2.016e-3
k = 0.437
mu = 3e-5
[]
[]
[Closures]
[closures]
type = Closures1PhaseSimple
[]
[]
[Components]
[bc_inlet]
type = InletMassFlowRateTemperature1Phase
input = 'ch_1:in'
m_dot = 0 # This value is controlled by 'mfr_ctrl'
T = ${T_in}
[]
[ch_1]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '1 0 0'
length = 0.5
n_elems = ${nelem}
A = ${area}
f = ${friction_factor}
fp = h2
[]
[junction]
type = JunctionOneToOne1Phase
connections = 'ch_1:out ch_2:in'
[]
[ch_2]
type = FlowChannel1Phase
position = '0.5 0 0'
orientation = '1 0 0'
length = 0.5
n_elems = ${nelem}
A = ${area}
f = ${friction_factor}
fp = h2
[]
[bc_outlet]
type = Outlet1Phase
input = 'ch_2:out'
p = ${p_out}
[]
[]
[Functions]
[mfr_fn]
type = PiecewiseLinear
x = '0 ${ramp_time}'
y = '0 ${mfr_final}'
[]
[]
[ControlLogic]
[mfr_cntrl]
type = TimeFunctionComponentControl
component = bc_inlet
parameter = m_dot
function = mfr_fn
[]
[]
[Preconditioning]
[pc]
type = SMP
full = true
[]
[]
[VectorPostprocessors]
[pressure_vpp]
type = ADSampler1DReal
block = 'ch_1 ch_2'
property = 'p'
sort_by = x
execute_on = 'FINAL'
[]
[]
[Executioner]
type = Transient
scheme = bdf2
start_time = 0
end_time = 50
dt = 1
steady_state_detection = true
steady_state_start_time = ${ramp_time}
petsc_options_iname = '-pc_type'
petsc_options_value = ' lu '
nl_rel_tol = 1e-6
nl_abs_tol = 1e-6
nl_max_its = 15
l_tol = 1e-4
l_max_its = 10
[]
[Outputs]
[csv]
type = CSV
create_final_symlink = true
execute_on = 'FINAL'
[]
[]
(modules/thermal_hydraulics/test/tests/components/junction_one_to_one_1phase/junction_one_to_one_1phase.i)
# This input file simulates the Sod shock tube using a junction in the middle
# of the domain. The solution should be exactly equivalent to the problem with
# no junction. This test examines the solutions at the junction connections
# and compares them to gold values generated from a version of this input file
# that has no junction.
[GlobalParams]
gravity_vector = '0 0 0'
closures = simple_closures
[]
[Functions]
[p_ic_fn]
type = PiecewiseConstant
axis = x
direction = right
x = '0.5 1.0'
y = '1.0 0.1'
[]
[T_ic_fn]
type = PiecewiseConstant
axis = x
direction = right
x = '0.5 1.0'
y = '1.4 1.12'
[]
[]
[FluidProperties]
[fp]
type = IdealGasFluidProperties
gamma = 1.4
molar_mass = 11.64024372
[]
[]
[Closures]
[simple_closures]
type = Closures1PhaseSimple
[]
[]
[Components]
[left_boundary]
type = FreeBoundary1Phase
input = 'left_channel:in'
[]
[left_channel]
type = FlowChannel1Phase
fp = fp
position = '0 0 0'
orientation = '1 0 0'
length = 0.5
n_elems = 50
A = 1.0
initial_T = T_ic_fn
initial_p = p_ic_fn
initial_vel = 0
f = 0
[]
[junction]
type = JunctionOneToOne1Phase
connections = 'left_channel:out right_channel:in'
[]
[right_channel]
type = FlowChannel1Phase
fp = fp
position = '0.5 0 0'
orientation = '1 0 0'
length = 0.5
n_elems = 50
A = 1.0
initial_T = T_ic_fn
initial_p = p_ic_fn
initial_vel = 0
f = 0
[]
[right_boundary]
type = FreeBoundary1Phase
input = 'right_channel:out'
[]
[]
[Preconditioning]
[smp]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
scheme = bdf2
solve_type = NEWTON
nl_rel_tol = 1e-10
nl_abs_tol = 1e-8
nl_max_its = 60
l_tol = 1e-4
start_time = 0.0
dt = 1e-3
num_steps = 5
abort_on_solve_fail = true
[]
[Postprocessors]
[rhoA_left]
type = SideAverageValue
variable = rhoA
boundary = left_channel:out
execute_on = 'initial timestep_end'
[]
[rhouA_left]
type = SideAverageValue
variable = rhouA
boundary = left_channel:out
execute_on = 'initial timestep_end'
[]
[rhoEA_left]
type = SideAverageValue
variable = rhoEA
boundary = left_channel:out
execute_on = 'initial timestep_end'
[]
[rhoA_right]
type = SideAverageValue
variable = rhoA
boundary = right_channel:in
execute_on = 'initial timestep_end'
[]
# rhouA_right is added by tests file
[rhoEA_right]
type = SideAverageValue
variable = rhoEA
boundary = right_channel:in
execute_on = 'initial timestep_end'
[]
# This is present to test that junction sidesets work properly
[p_avg_junction]
type = SideAverageValue
boundary = 'junction'
variable = p
execute_on = 'initial timestep_end'
[]
[]
[Outputs]
csv = true
show = 'rhoA_left rhouA_left rhoEA_left rhoA_right rhouA_right rhoEA_right'
execute_on = 'initial timestep_end'
[]
(modules/thermal_hydraulics/tutorials/single_phase_flow/03_upper_loop.i)
T_in = 300. # K
m_dot_in = 1e-2 # kg/s
press = 10e5 # Pa
# core parameters
core_length = 1. # m
core_n_elems = 25
core_dia = '${units 2. cm -> m}'
core_pitch = '${units 8.7 cm -> m}'
A_core = '${fparse core_pitch^2 - 0.25 *pi * core_dia^2}'
P_wet_core = '${fparse 4*core_pitch + pi * core_dia}'
Dh_core = '${fparse 4 * A_core / P_wet_core}'
# pipe parameters
pipe_dia = '${units 10. cm -> m}'
A_pipe = '${fparse 0.25 * pi * pipe_dia^2}'
tot_power = 2000 # W
[GlobalParams]
initial_p = ${press}
initial_vel = 0.0001
initial_T = ${T_in}
initial_vel_x = 0
initial_vel_y = 0
initial_vel_z = 0
gravity_vector = '0 0 0'
rdg_slope_reconstruction = minmod
scaling_factor_1phase = '1 1e-2 1e-4'
scaling_factor_rhoV = 1
scaling_factor_rhouV = 1e-2
scaling_factor_rhovV = 1e-2
scaling_factor_rhowV = 1e-2
scaling_factor_rhoEV = 1e-4
closures = thm_closures
fp = he
[]
[FluidProperties]
[he]
type = IdealGasFluidProperties
molar_mass = 4e-3
gamma = 1.67
k = 0.2556
mu = 3.22639e-5
[]
[]
[Closures]
[thm_closures]
type = Closures1PhaseTHM
[]
[]
[SolidProperties]
[steel]
type = ThermalFunctionSolidProperties
rho = 8050
k = 45
cp = 466
[]
[]
[Components]
[total_power]
type = TotalPower
power = ${tot_power}
[]
[inlet]
type = InletMassFlowRateTemperature1Phase
input = 'up_pipe_1:in'
m_dot = ${m_dot_in}
T = ${T_in}
[]
[up_pipe_1]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '0 0 1'
length = 0.5
n_elems = 15
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct1]
type = JunctionParallelChannels1Phase
position = '0 0 0.5'
connections = 'up_pipe_1:out core_chan:in'
volume = 1e-5
use_scalar_variables = false
[]
[core_chan]
type = FlowChannel1Phase
position = '0 0 0.5'
orientation = '0 0 1'
length = ${core_length}
n_elems = ${core_n_elems}
roughness = .0001
A = '${A_core}'
D_h = ${Dh_core}
[]
[core_hs]
type = HeatStructureCylindrical
position = '0 0 0.5'
orientation = '0 0 1'
length = ${core_length}
n_elems = ${core_n_elems}
names = 'block'
widths = '${fparse core_dia / 2.}'
solid_properties = 'steel'
solid_properties_T_ref = '300'
n_part_elems = 3
[]
[core_heating]
type = HeatSourceFromTotalPower
hs = core_hs
regions = block
power = total_power
[]
[core_ht]
type = HeatTransferFromHeatStructure1Phase
flow_channel = core_chan
hs = core_hs
hs_side = outer
P_hf = '${fparse pi * core_dia}'
[]
[jct2]
type = JunctionParallelChannels1Phase
position = '0 0 1.5'
connections = 'core_chan:out up_pipe_2:in'
volume = 1e-5
use_scalar_variables = false
[]
[up_pipe_2]
type = FlowChannel1Phase
position = '0 0 1.5'
orientation = '0 0 1'
length = 0.5
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct3]
type = JunctionOneToOne1Phase
connections = 'up_pipe_2:out top_pipe:in'
[]
[top_pipe]
type = FlowChannel1Phase
position = '0 0 2'
orientation = '1 0 0'
length = 1
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[jct4]
type = JunctionOneToOne1Phase
connections = 'top_pipe:out down_pipe_1:in'
[]
[down_pipe_1]
type = FlowChannel1Phase
position = '1 0 2'
orientation = '0 0 -1'
length = 0.25
A = ${A_pipe}
n_elems = 5
[]
[jct5]
type = JunctionOneToOne1Phase
connections = 'down_pipe_1:out cooling_pipe:in'
[]
[cooling_pipe]
type = FlowChannel1Phase
position = '1 0 1.75'
orientation = '0 0 -1'
length = 1.5
n_elems = 25
A = ${A_pipe}
[]
[cold_wall]
type = HeatTransferFromSpecifiedTemperature1Phase
flow_channel = cooling_pipe
T_wall = 300
P_hf = '${fparse pi * pipe_dia}'
[]
[jct6]
type = JunctionOneToOne1Phase
connections = 'cooling_pipe:out down_pipe_2:in'
[]
[down_pipe_2]
type = FlowChannel1Phase
position = '1 0 0.25'
orientation = '0 0 -1'
length = 0.25
n_elems = 10
A = ${A_pipe}
D_h = ${pipe_dia}
[]
[outlet]
type = Outlet1Phase
input = 'down_pipe_2:out'
p = ${press}
[]
[]
[Postprocessors]
[power_to_coolant]
type = ADHeatRateConvection1Phase
block = core_chan
P_hf = '${fparse pi *core_dia}'
[]
[core_T_out]
type = SideAverageValue
boundary = core_chan:out
variable = T
[]
[core_p_in]
type = SideAverageValue
boundary = core_chan:in
variable = p
[]
[core_p_out]
type = SideAverageValue
boundary = core_chan:out
variable = p
[]
[core_delta_p]
type = ParsedPostprocessor
pp_names = 'core_p_in core_p_out'
expression = 'core_p_in - core_p_out'
[]
[hx_pri_T_out]
type = SideAverageValue
boundary = cooling_pipe:out
variable = T
[]
[]
[Preconditioning]
[pc]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
start_time = 0
[TimeStepper]
type = IterationAdaptiveDT
dt = 1
[]
end_time = 500
line_search = basic
solve_type = NEWTON
petsc_options_iname = '-pc_type'
petsc_options_value = 'lu'
nl_rel_tol = 1e-8
nl_abs_tol = 1e-8
nl_max_its = 25
[]
[Outputs]
exodus = true
[console]
type = Console
max_rows = 1
outlier_variable_norms = false
[]
print_linear_residuals = false
[]