- K_dCoefficient for the derivative term
C++ Type:Real
Unit:(no unit assumed)
Controllable:No
Description:Coefficient for the derivative term
- K_iCoefficient for the integral term
C++ Type:Real
Unit:(no unit assumed)
Controllable:No
Description:Coefficient for the integral term
- K_pCoefficient for the proportional term
C++ Type:Real
Unit:(no unit assumed)
Controllable:No
Description:Coefficient for the proportional term
- inputInput control data
C++ Type:std::string
Controllable:No
Description:Input control data
- set_pointSet point control data
C++ Type:std::string
Controllable:No
Description:Set point control data
PIDChainControl
This ChainControl implements the classic PID controller, which takes as its input a value and the set point for that value, . It produces an output signal , which should be used as the input for some controllable device that impacts the measured quantity . For example, in a thermal system, may be the temperature of a fluid at some location, and may be the power sent to the heaters in the system, with the goal to heat the fluid such that the temperature at some location is .
"PID" stands for its three components:
P: Proportional
I: Integral
D: Derivative
The output signal at time is computed as follows:
where is the time step size and is the error:
warningwarning:Execute only once per time step
The implementation assumes that the control will only be executed once per time step, so you should set "execute_on" accordingly, such as execute_on = 'INITIAL TIMESTEP_END', which is the default.
The inputs and outputs are retrieved and named as follows, respectively:
is set with "input".
is set with "set_point".
is declared with the name
<control_name>:value, where<control_name>is the user-given name of thePIDChainControl.
schooltip:Tuning PID coefficients
If you are unsure on how to select the PID coefficients , , and , you may try the following strategy, which involves some trial and error. First, set and to zero. Then, set to some arbitrary (positive) value. Run a simulation with and examine the transient response of to the set point value . The goal should be to maximize without causing an unstable response, where oscillates indefinitely around . Some initial overshoot and subsequent diminishing oscillations are acceptable. After this acceptable value of is found, you'll likely find that appears to be nearly constant in time, but at the wrong value. At this point, you should start increasing from zero until you get an acceptable response time to get the initial response (largely driven by ) to bridge the gap to , without introducing oscillatory behavior. Lastly, can be used to fine-tune the response, but it is not necessary, and it risks some oscillatory behavior if the inputs have any noise, so it should only be used for relatively smooth inputs.
commentnote
To control a controllable value directly instead of using a ChainControlData, use PIDTransientControl.
Input Parameters
- depends_onThe Controls that this control relies upon (i.e. must execute before this one)
C++ Type:std::vector<std::string>
Controllable:No
Description:The Controls that this control relies upon (i.e. must execute before this one)
- execute_onINITIAL TIMESTEP_ENDThe list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.
Default:INITIAL TIMESTEP_END
C++ Type:ExecFlagEnum
Options:XFEM_MARK, FORWARD, ADJOINT, HOMOGENEOUS_FORWARD, ADJOINT_TIMESTEP_BEGIN, ADJOINT_TIMESTEP_END, NONE, INITIAL, LINEAR, LINEAR_CONVERGENCE, NONLINEAR, NONLINEAR_CONVERGENCE, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, MULTIAPP_FIXED_POINT_CONVERGENCE, MULTISYSTEM_FIXED_POINT_ITERATION_END, FINAL, FAILED, CUSTOM, PRE_MULTIAPP_SETUP
Controllable:No
Description:The list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.
- initial_integral0Initial value for the integral component
Default:0
C++ Type:Real
Unit:(no unit assumed)
Controllable:No
Description:Initial value for the integral component
Optional Parameters
- control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
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
Controllable:No
Description:Set the enabled status of the MooseObject.
- implicitTrueDetermines whether this object is calculated using an implicit or explicit form
Default:True
C++ Type:bool
Controllable:No
Description:Determines whether this object is calculated using an implicit or explicit form
Advanced Parameters
Input Files
- (modules/thermal_hydraulics/tutorials/single_phase_flow/06_custom_closures.i)
- (modules/thermal_hydraulics/test/tests/components/shaft_connected_turbine_1phase/turbine_startup.i)
- (modules/thermal_hydraulics/tutorials/single_phase_flow/05_secondary_side.i)
- (test/tests/chaincontrols/pid_chain_control/pid_chain_control.i)
- (modules/thermal_hydraulics/tutorials/single_phase_flow/04_loop.i)
- (modules/thermal_hydraulics/test/tests/problems/brayton_cycle/recuperated_brayton_cycle.i)
execute_on
Default:INITIAL TIMESTEP_END
C++ Type:ExecFlagEnum
Options:XFEM_MARK, FORWARD, ADJOINT, HOMOGENEOUS_FORWARD, ADJOINT_TIMESTEP_BEGIN, ADJOINT_TIMESTEP_END, NONE, INITIAL, LINEAR, LINEAR_CONVERGENCE, NONLINEAR, NONLINEAR_CONVERGENCE, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, MULTIAPP_FIXED_POINT_CONVERGENCE, MULTISYSTEM_FIXED_POINT_ITERATION_END, FINAL, FAILED, CUSTOM, PRE_MULTIAPP_SETUP
Controllable:No
Description:The list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.
input
C++ Type:std::string
Controllable:No
Description:Input control data
set_point
C++ Type:std::string
Controllable:No
Description:Set point control data
(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
[]
[]
[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
[]
[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
[]
[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'
[]
[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
[]
[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 = ${hx_dia_inner}
closures = ''
[]
[ht_pri]
type = HeatTransferFromHeatStructure1Phase
hs = hx/wall
hs_side = inner
flow_channel = hx/pri
P_hf = '${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
[]
[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
[]
[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
[]
[]
[ChainControls]
[get_m_dot_pump]
type = GetPostprocessorChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
postprocessor = m_dot_pump
name_data_same_as_postprocessor = true
[]
[set_point]
type = GetFunctionValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
function = ${m_dot_in}
[]
[pid]
type = PIDChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
initial_integral = 0.0
set_point = set_point:value
input = m_dot_pump
K_p = 1.
K_i = 4.
K_d = 0
[]
[set_pump_head]
type = SetRealValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
parameter = component::pump/head
value = pid:value
[]
[m_dot_sec_inlet_ctrl]
type = GetFunctionValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
function = m_dot_sec_fn
[]
[set_m_dot_sec_ctrl]
type = SetRealValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
parameter = component::inlet_sec/m_dot
value = m_dot_sec_inlet_ctrl:value
[]
[]
[Postprocessors]
[power_to_coolant]
type = ADHeatRateConvection1Phase
block = core_chan
P_hf = '${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/components/shaft_connected_turbine_1phase/turbine_startup.i)
# This test tests that the turbine can startup from rest and reach full power.
# The mass flow rate for the inlet component is ramped up over 10s. The dyno
# component and pid_ctrl controler are used to maintain the turbine's rated shaft
# speed. The turbine should supply ~1e6 W of power to the shaft by the end of the test.
omega_rated = 450
mdot = 5.0
T_in = 1000.0
p_out = 1e6
[GlobalParams]
f = 1
scaling_factor_1phase = '0.04 0.04 0.04e-5'
closures = simple_closures
n_elems = 20
initial_T = ${T_in}
initial_p = ${p_out}
initial_vel = 0
initial_vel_x = 0
initial_vel_y = 0
initial_vel_z = 0
[]
[FluidProperties]
[eos]
type = IdealGasFluidProperties
[]
[]
[Closures]
[simple_closures]
type = Closures1PhaseSimple
[]
[]
[Components]
[ch_in]
type = FlowChannel1Phase
position = '-1 0 0'
orientation = '1 0 0'
length = 1
A = 0.1
D_h = 1
fp = eos
[]
[inlet]
type = InletMassFlowRateTemperature1Phase
input = 'ch_in:in'
m_dot = 0
T = ${T_in}
[]
[turbine]
type = ShaftConnectedTurbine1Phase
inlet = 'ch_in:out'
outlet = 'ch_out:in'
position = '0 0 0'
scaling_factor_rhoEV = 1e-5
A_ref = 0.1
volume = 0.0002
inertia_coeff = '1 1 1 1'
inertia_const = 1.61397
speed_cr_I = 1e12
speed_cr_fr = 0
tau_fr_coeff = '0 0 0 0'
tau_fr_const = 0
omega_rated = ${omega_rated}
D_wheel = 0.4
head_coefficient = head
power_coefficient = power
[]
[ch_out]
type = FlowChannel1Phase
position = '0 0 0'
orientation = '1 0 0'
length = 1
A = 0.1
D_h = 1
fp = eos
[]
[outlet]
type = Outlet1Phase
input = 'ch_out:out'
p = ${p_out}
[]
[dyno]
type = ShaftConnectedMotor
inertia = 10
torque = dyno_torque_fn
[]
[shaft]
type = Shaft
connected_components = 'turbine dyno'
initial_speed = ${omega_rated}
[]
[]
[Functions]
[head]
type = PiecewiseLinear
x = '0 7e-3 1e-2'
y = '0 15 20'
[]
[power]
type = PiecewiseLinear
x = '0 6e-3 1e-2'
y = '0 0.05 0.18'
[]
[mfr_fn]
type = PiecewiseLinear
x = '0 10'
y = '1e-6 ${mdot}'
[]
[dts]
type = PiecewiseConstant
y = '5e-3 1e-2 5e-2 5e-1'
x = '0 0.5 1 10'
[]
[dyno_torque_fn]
type = ConstantFunction
value = -450 # controlled
[]
[]
[ChainControls]
[mfr_cntrl_fn]
type = GetFunctionValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
function = mfr_fn
[]
[mfr_cntrl]
type = SetRealValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
parameter = component::inlet/m_dot
value = mfr_cntrl_fn:value
[]
[get_omega]
type = GetPostprocessorChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
postprocessor = omega
name_data_same_as_postprocessor = true
[]
[speed_set_point]
type = GetFunctionValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
function = ${omega_rated}
[]
[pid_ctrl]
type = PIDChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
input = omega
set_point = speed_set_point:value
K_i = 2
K_p = 5
K_d = 5
initial_integral = -450
[]
[set_torque_value]
type = SetRealValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
parameter = Functions/dyno_torque_fn/value
value = pid_ctrl:value
[]
[]
[Postprocessors]
[omega]
type = ScalarVariable
variable = shaft:omega
execute_on = 'initial timestep_end'
[]
[flow_coefficient]
type = ElementAverageValue
variable = flow_coeff
block = 'turbine'
execute_on = 'initial timestep_end'
[]
[delta_p]
type = ElementAverageValue
variable = delta_p
block = 'turbine'
execute_on = 'initial timestep_end'
[]
[power]
type = ElementAverageValue
variable = power
block = 'turbine'
execute_on = 'initial timestep_end'
[]
[]
[Preconditioning]
[SMP]
type = SMP
full = true
[]
[]
[Executioner]
type = Transient
scheme = 'implicit-euler'
start_time = 0
[TimeStepper]
type = FunctionDT
function = dts
[]
end_time = 20
abort_on_solve_fail = true
solve_type = 'PJFNK'
line_search = 'basic'
nl_rel_tol = 1e-6
nl_abs_tol = 1e-4
nl_max_its = 30
l_tol = 1e-4
l_max_its = 20
[Quadrature]
type = GAUSS
order = SECOND
[]
[]
[Outputs]
[console]
type = Console
max_rows = 1
[]
print_linear_residuals = false
[]
(modules/thermal_hydraulics/tutorials/single_phase_flow/05_secondary_side.i)
T_in = 300. # K
m_dot_in = 1e-2 # kg/s
press = 10e5 # Pa
# core parameters
core_length = 1. # m
core_n_elems = 25
core_dia = '${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
[]
[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
[]
[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'
[]
[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
[]
[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
[]
[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
[]
[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
[]
[]
[ChainControls]
[get_m_dot_pump]
type = GetPostprocessorChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
postprocessor = m_dot_pump
name_data_same_as_postprocessor = true
[]
[set_point]
type = GetFunctionValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
function = ${m_dot_in}
[]
[pid]
type = PIDChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
initial_integral = 0.0
set_point = set_point:value
input = m_dot_pump
K_p = 1.
K_i = 4.
K_d = 0
[]
[set_pump_head]
type = SetRealValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
parameter = component::pump/head
value = pid:value
[]
[m_dot_sec_inlet_ctrl]
type = GetFunctionValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
function = m_dot_sec_fn
[]
[set_m_dot_sec_ctrl]
type = SetRealValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
parameter = component::inlet_sec/m_dot
value = m_dot_sec_inlet_ctrl:value
[]
[]
[Postprocessors]
[power_to_coolant]
type = ADHeatRateConvection1Phase
block = core_chan
P_hf = '${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
[]
(test/tests/chaincontrols/pid_chain_control/pid_chain_control.i)
# Tests PIDChainControl
#
# The PID controller is used to solve the equation y(alpha) = alpha^2 = 25 for alpha.
# Each time step takes one iteration, and these iterations should be converging to alpha = 5.
[Mesh]
type = GeneratedMesh
dim = 1
nx = 1
[]
[ChainControls]
[get_alpha_ctrl]
type = GetPostprocessorChainControl
postprocessor = pid
[]
[y_ctrl]
type = ParsedChainControl
expression = 'alpha^2'
symbol_names = 'alpha'
symbol_values = 'get_alpha_ctrl:value'
[]
[y_set_ctrl]
type = ParsedChainControl
expression = '25'
[]
[pid_ctrl]
type = PIDChainControl
input = y_ctrl:value
set_point = y_set_ctrl:value
K_p = 0.1
K_i = 0.01
K_d = 0.001
[]
[]
[Postprocessors]
[pid]
type = ChainControlDataPostprocessor
chain_control_data_name = pid_ctrl:value
execute_on = 'INITIAL TIMESTEP_END'
[]
[]
[Problem]
solve = false
[]
[Executioner]
type = Transient
dt = 1
num_steps = 50
[]
[Outputs]
csv = true
[]
(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
[]
[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
[]
[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'
[]
[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
[]
[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'
[]
[]
[ChainControls]
[get_m_dot_pump]
type = GetPostprocessorChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
postprocessor = m_dot_pump
name_data_same_as_postprocessor = true
[]
[set_point]
type = GetFunctionValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
function = ${m_dot_in}
[]
[pid]
type = PIDChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
initial_integral = 0
set_point = set_point:value
input = m_dot_pump
K_p = 1.
K_i = 4.
K_d = 0
[]
[set_pump_head]
type = SetRealValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
parameter = component::pump/head
value = pid:value
[]
[]
[Postprocessors]
[power_to_coolant]
type = ADHeatRateConvection1Phase
block = core_chan
P_hf = '${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 = 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/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 = ${T_ambient}
initial_vel = 0
initial_vel_x = 0
initial_vel_y = 0
initial_vel_z = 0
fp = fp_air
closures = closures
f = 0
scaling_factor_1phase = '1 1 1e-5'
scaling_factor_rhoV = 1
scaling_factor_rhouV = 1e-2
scaling_factor_rhovV = 1e-2
scaling_factor_rhowV = 1e-2
scaling_factor_rhoEV = 1e-5
scaling_factor_temperature = 1e-2
rdg_slope_reconstruction = none
[]
[FluidProperties]
[fp_air]
type = IdealGasFluidProperties
emit_on_nan = none
[]
[]
[SolidProperties]
[steel]
type = ThermalFunctionSolidProperties
rho = 8050
k = 45
cp = 466
[]
[]
[Closures]
[closures]
type = Closures1PhaseSimple
[]
[]
[Functions]
##########################
# Motor
##########################
# Functions for control logic that determines when to shut off the PID system
[is_tripped_fn]
type = ParsedFunction
symbol_names = 'motor_torque turbine_torque'
symbol_values = 'motor_torque turbine_torque'
expression = 'turbine_torque > motor_torque'
[]
[PID_tripped_constant_value]
type = ConstantFunction
value = 1
[]
[PID_tripped_status_fn]
type = ParsedFunction
symbol_values = 'PID_trip_status'
symbol_names = 'PID_trip_status'
expression = 'PID_trip_status'
[]
[time_fn]
type = ParsedFunction
expression = t
[]
# Shutdown function which ramps down the motor once told by the control logic
[motor_torque_fn_shutdown]
type = ParsedFunction
symbol_values = 'PID_trip_status time_trip'
symbol_names = 'PID_trip_status time_trip'
expression = 'if(PID_trip_status = 1, max(2.4 - (2.4 * ((t - time_trip) / 35000)),0.0), 1)'
[]
[motor_torque_fn]
type = ConstantFunction
value = 0 # controlled
[]
# Generates motor power curve
[motor_power_fn]
type = ParsedFunction
expression = 'torque * speed'
symbol_names = 'torque speed'
symbol_values = 'motor_torque shaft:omega'
[]
##########################
# Generator
##########################
# Generates generator torque curve
[generator_torque_fn]
type = ParsedFunction
expression = 'slope * t'
symbol_names = 'slope'
symbol_values = '${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'
[]
# 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 = ${fparse A2*0.1}
[]
# Cold leg of the recuperator
[cold_leg]
type = FlowChannel1Phase
position = '${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 = ${fparse A3*0.1}
[]
# Pipe through the "reactor core"
[pipe4]
type = FlowChannel1Phase
position = '${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 = ${fparse A4*0.1}
[]
# Pipe carrying hot gas back to the PCU
[pipe5]
type = FlowChannel1Phase
position = '${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 = ${fparse A5*0.1}
[]
# Inlet pipe to the turbine
[pipe6]
type = FlowChannel1Phase
position = '${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'
[]
# 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 = ${fparse A7*0.1}
[]
# Hot leg of the recuperator
[hot_leg]
type = FlowChannel1Phase
position = '${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
[ChainControls]
# Bring the postprocessors used by the controls into the control data system
[get_shaft_RPM]
type = GetPostprocessorChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
postprocessor = shaft_RPM
name_data_same_as_postprocessor = true
[]
[get_motor_torque]
type = GetPostprocessorChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
postprocessor = motor_torque
name_data_same_as_postprocessor = true
[]
[get_turbine_torque]
type = GetPostprocessorChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
postprocessor = turbine_torque
name_data_same_as_postprocessor = true
[]
# Sets desired shaft speed to be reached by motor NOTE: SHOULD BE SET LOWER THAN RATED TURBINE RPM
[set_point]
type = GetFunctionValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
function = ${fparse speed_rated_rpm - 9000}
[]
# PID with gains determined by iterative process NOTE: Gain values are system specific
[initial_motor_PID]
type = PIDChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
set_point = set_point:value
input = shaft_RPM
initial_integral = 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 = ParsedChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
expression = 'if(motor+0.5 > turb, PID, shutdown_fn)'
symbol_names = 'motor turb PID shutdown_fn'
symbol_values = 'motor_torque turbine_torque initial_motor_PID:value motor_torque_fn_shutdown'
[]
# Takes the output generated in [logic] and applies it to the motor torque
[motor_PID]
type = SetRealValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
parameter = Functions/motor_torque_fn/value
value = logic:value
[]
# Determines when to turn on heat source
[power_logic]
type = ParsedChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
expression = 'power_fn'
symbol_names = 'power_fn'
symbol_values = 'power_fn'
[]
# Applies heat source to the total_power block
[power_applied]
type = SetRealValueChainControl
execute_on = 'INITIAL TIMESTEP_BEGIN'
parameter = component::total_power/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 = ShaftConnectedComponentPostprocessor
quantity = torque
shaft_connected_component_uo = motor:shaftconnected_uo
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'
[]
[]