PresetAcceleration Class Reference

This class prescribes the acceleration on a given boundary in a given direction. More...

#include <PresetAcceleration.h>

Inheritance diagram for PresetAcceleration:

Public Member Functions
	PresetAcceleration (const InputParameters &parameters)

Static Public Member Functions
static InputParameters	validParams ()

Protected Member Functions
virtual Real	computeQpValue ()

Protected Attributes
const VariableValue &	_u_old
const Real	_scale_factor
const Function &	_function
const VariableValue &	_vel_old
const VariableValue &	_accel_old
const Real	_beta

Detailed Description

This class prescribes the acceleration on a given boundary in a given direction.

The acceleration is integrated using newmark time integration scheme and the resulting displacement is applied on the boundary.

Definition at line 20 of file PresetAcceleration.h.

Constructor & Destructor Documentation

PresetAcceleration()

PresetAcceleration::PresetAcceleration

(

const InputParameters &

parameters

)

Definition at line 36 of file PresetAcceleration.C.

  : DirichletBCBase(parameters),
    _u_old(valueOld()),
    _scale_factor(parameters.get<Real>("scale_factor")),
    _function(getFunction("function")),
    _vel_old(coupledValueOld("velocity")),
    _accel_old(coupledValueOld("acceleration")),
    _beta(getParam<Real>("beta"))
{
}

Member Function Documentation

computeQpValue()

Real PresetAcceleration::computeQpValue ( )

protectedvirtual

Definition at line 48 of file PresetAcceleration.C.

{
  Real accel = _function.value(_t, *_current_node);
 
  // Integrate acceleration using Newmark time integration to get displacement
  return _u_old[_qp] + _dt * _vel_old[_qp] +
         ((0.5 - _beta) * _accel_old[_qp] + _beta * accel) * _dt * _dt;
}

validParams()

InputParameters PresetAcceleration::validParams ( )

static

Definition at line 18 of file PresetAcceleration.C.

{
  InputParameters params = DirichletBCBase::validParams();
  params.addClassDescription("Prescribe acceleration on a given boundary in a given direction");
 
  params.addParam<Real>("scale_factor", 1, "Scale factor if function is given.");
  params.addParam<FunctionName>("function", "1", "Function describing the velocity.");
  params.addRequiredCoupledVar("velocity", "The velocity variable.");
  params.addRequiredCoupledVar("acceleration", "The acceleration variable.");
  params.addRequiredParam<Real>("beta", "beta parameter for Newmark time integration.");
 
  // Forcefully preset the BC
  params.set<bool>("preset") = true;
  params.suppressParameter<bool>("preset");
 
  return params;
}

Member Data Documentation

_accel_old

const VariableValue& PresetAcceleration::_accel_old

protected

Definition at line 34 of file PresetAcceleration.h.

Referenced by computeQpValue().

_beta

const Real PresetAcceleration::_beta

protected

Definition at line 35 of file PresetAcceleration.h.

Referenced by computeQpValue().

_function

const Function& PresetAcceleration::_function

protected

Definition at line 32 of file PresetAcceleration.h.

Referenced by computeQpValue().

_scale_factor

const Real PresetAcceleration::_scale_factor

protected

Definition at line 31 of file PresetAcceleration.h.

_u_old

const VariableValue& PresetAcceleration::_u_old

protected

Definition at line 30 of file PresetAcceleration.h.

Referenced by computeQpValue().

_vel_old

const VariableValue& PresetAcceleration::_vel_old

protected

Definition at line 33 of file PresetAcceleration.h.

Referenced by computeQpValue().

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The documentation for this class was generated from the following files:

• tensor_mechanics/include/bcs/PresetAcceleration.h
• tensor_mechanics/src/bcs/PresetAcceleration.C