EulerAngleUpdaterCheck Class Reference

This is a unit test to check the correctness of the updated euler angles An unit vector is rotated as per old euler angles first and then due to the applied torque The final rotated vector is cross checked with the rotated vector as per updated euler angles. More...

#include <EulerAngleUpdaterCheck.h>

Inheritance diagram for EulerAngleUpdaterCheck:

Public Member Functions
	EulerAngleUpdaterCheck (const InputParameters &parameters)
virtual void	initialize () override
virtual void	execute () override
virtual void	finalize () override

Public Attributes
VectorPostprocessorValue &	_diff

Protected Attributes
const GrainTrackerInterface &	_grain_tracker
const EulerAngleUpdater &	_euler
const GrainForceAndTorqueInterface &	_grain_torque
const VectorPostprocessorValue &	_grain_volumes
const Real	_mr
std::vector< RealVectorValue >	_angles
std::vector< RealVectorValue >	_angles_old

Detailed Description

This is a unit test to check the correctness of the updated euler angles An unit vector is rotated as per old euler angles first and then due to the applied torque The final rotated vector is cross checked with the rotated vector as per updated euler angles.

Definition at line 30 of file EulerAngleUpdaterCheck.h.

Constructor & Destructor Documentation

EulerAngleUpdaterCheck()

EulerAngleUpdaterCheck::EulerAngleUpdaterCheck

(

const InputParameters &

parameters

)

Definition at line 38 of file EulerAngleUpdaterCheck.C.

  : GeneralVectorPostprocessor(params),
    _diff(declareVector("vec_diff")),
    _grain_tracker(getUserObject<GrainTrackerInterface>("grain_tracker_object")),
    _euler(getUserObject<EulerAngleUpdater>("euler_angle_updater")),
    _grain_torque(getUserObject<GrainForceAndTorqueInterface>("grain_torques_object")),
    _grain_volumes(getVectorPostprocessorValue("grain_volumes", "feature_volumes")),
    _mr(getParam<Real>("rotation_constant"))
{
}

Member Function Documentation

execute()

virtual void EulerAngleUpdaterCheck::execute ( )

inlineoverridevirtual

Definition at line 36 of file EulerAngleUpdaterCheck.h.

{}

finalize()

virtual void EulerAngleUpdaterCheck::finalize ( )

inlineoverridevirtual

Definition at line 37 of file EulerAngleUpdaterCheck.h.

{}

initialize()

void EulerAngleUpdaterCheck::initialize ( )

overridevirtual

Change in euler angles are obtained from the torque & angular velocities about the material axes. Change in phi1, Phi and phi2 are caused by rotation about z axis, x' axis & z'' axis, respectively. Components of the angular velocities across z, x' and z'' axes are obtained from the torque values. This yields change in euler angles due to grain rotation.

Definition at line 50 of file EulerAngleUpdaterCheck.C.

{
  const auto grain_num = _grain_tracker.getTotalFeatureCount();
  _angles.resize(grain_num);
  _angles_old.resize(grain_num);
  _diff.assign(3 * grain_num, 0.0);
 
  for (unsigned int i = 0; i < grain_num; ++i)
  {
    _angles[i] = _euler.getEulerAngles(i);
    _angles_old[i] = _euler.getEulerAnglesOld(i);
    RealGradient torque = _grain_torque.getTorqueValues()[i];
 
    RealVectorValue a(1, 1, 1);
    RotationTensor R(_angles[i]);  // Final rotation tensor
    RealVectorValue a_rot = R * a; // final rotated vector
 
    RotationTensor R0(_angles_old[i]);        // RotationTensor as per old euler angles
    RealVectorValue torque_rot = R0 * torque; // Rotated torque
    RealVectorValue a_rot0 = R0 * a;          // Rotated unit vector as per old euler angles
 
    RealVectorValue torque_rot1;
    RealVectorValue angle_rot;
    torque_rot1(0) =
        torque_rot(2); // Tourque about z changed to torque responsible for chaneg in angle phi1
    angle_rot(0) = _mr / _grain_volumes[i] * torque_rot1(0) * _dt; // change in phi1
    // Tourque about x' changed to torque responsible for chaneg in angle Phi
    torque_rot1(1) =
        (torque_rot(0) * std::cos(angle_rot(0)) + torque_rot(1) * std::sin(angle_rot(0)));
    angle_rot(1) = _mr / _grain_volumes[i] * torque_rot1(1) * _dt; // change in Phi
    // Tourque about z'' changed to torque responsible for chaneg in angle phi2
    torque_rot1(2) = (torque_rot(0) * std::sin(angle_rot(0)) * std::sin(angle_rot(1)) -
                      torque_rot(1) * std::cos(angle_rot(0)) * std::sin(angle_rot(1)) +
                      torque_rot(2) * std::cos(angle_rot(1)));
    angle_rot(2) = _mr / _grain_volumes[i] * torque_rot1(2) * _dt; // change in phi2
    angle_rot *= (180.0 / libMesh::pi);
 
    RotationTensor R4(angle_rot);         // RotationTensor due to grain rotation
    RealVectorValue a_rot1 = R4 * a_rot0; // Final rotated vector obtained in two step rotation
 
    // Difference between the final positions of the rotated vector obtained in two different ways,
    // should be 0.0
    _diff[3 * i + 0] = a_rot(0) - a_rot1(0);
    _diff[3 * i + 1] = a_rot(1) - a_rot1(1);
    _diff[3 * i + 2] = a_rot(2) - a_rot1(2);
  }
}

Member Data Documentation

_angles

std::vector<RealVectorValue> EulerAngleUpdaterCheck::_angles

protected

Definition at line 49 of file EulerAngleUpdaterCheck.h.

Referenced by initialize().

_angles_old

std::vector<RealVectorValue> EulerAngleUpdaterCheck::_angles_old

protected

Definition at line 50 of file EulerAngleUpdaterCheck.h.

Referenced by initialize().

_diff

VectorPostprocessorValue& EulerAngleUpdaterCheck::_diff

Definition at line 39 of file EulerAngleUpdaterCheck.h.

Referenced by initialize().

_euler

const EulerAngleUpdater& EulerAngleUpdaterCheck::_euler

protected

Definition at line 43 of file EulerAngleUpdaterCheck.h.

Referenced by initialize().

_grain_torque

const GrainForceAndTorqueInterface& EulerAngleUpdaterCheck::_grain_torque

protected

Definition at line 44 of file EulerAngleUpdaterCheck.h.

Referenced by initialize().

_grain_tracker

const GrainTrackerInterface& EulerAngleUpdaterCheck::_grain_tracker

protected

Definition at line 42 of file EulerAngleUpdaterCheck.h.

Referenced by initialize().

_grain_volumes

const VectorPostprocessorValue& EulerAngleUpdaterCheck::_grain_volumes

protected

Definition at line 45 of file EulerAngleUpdaterCheck.h.

Referenced by initialize().

_mr

const Real EulerAngleUpdaterCheck::_mr

protected

Definition at line 47 of file EulerAngleUpdaterCheck.h.

Referenced by initialize().

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

• phase_field/include/vectorpostprocessors/EulerAngleUpdaterCheck.h
• phase_field/src/vectorpostprocessors/EulerAngleUpdaterCheck.C