IBAMR::FEMechanicsExplicitIntegrator Class Reference

Class FEMechanicsExplicitIntegrator is an implementation of the abstract base class FEMechanicsBase that provides a simple explicit elastodynamics time integrator with an interface that is similar to IBFEMethod to facilitate model re-use. More...

#include </home/runner/work/IBAMR/IBAMR/include/ibamr/FEMechanicsExplicitIntegrator.h>

Inheritance diagram for IBAMR::FEMechanicsExplicitIntegrator:

Public Member Functions
	FEMechanicsExplicitIntegrator (const std::string &object_name, const SAMRAI::tbox::Pointer< SAMRAI::tbox::Database > &input_db, libMesh::MeshBase *mesh, bool register_for_restart=true, const std::string &restart_read_dirname="", unsigned int restart_restore_number=0)
	Constructor for a single-part model.
	FEMechanicsExplicitIntegrator (const std::string &object_name, const SAMRAI::tbox::Pointer< SAMRAI::tbox::Database > &input_db, const std::vector< libMesh::MeshBase * > &meshes, bool register_for_restart=true, const std::string &restart_read_dirname="", unsigned int restart_restore_number=0)
	Constructor for a multi-part model.
	FEMechanicsExplicitIntegrator ()=delete
	Deleted default constructor.
	FEMechanicsExplicitIntegrator (const FEMechanicsExplicitIntegrator &from)=delete
	Deleted copy constructor.
FEMechanicsExplicitIntegrator &	operator= (const FEMechanicsExplicitIntegrator &that)=delete
	Deleted assignment operator.
	~FEMechanicsExplicitIntegrator () override=default
	Defaulted destructor.
void	preprocessIntegrateData (double current_time, double new_time, int num_cycles) override
void	postprocessIntegrateData (double current_time, double new_time, int num_cycles) override
void	forwardEulerStep (double current_time, double new_time)
void	modifiedEulerStep (double current_time, double new_time)
void	backwardEulerStep (double current_time, double new_time)
void	midpointStep (double current_time, double new_time)
void	trapezoidalStep (double current_time, double new_time)
void	modifiedTrapezoidalStep (double current_time, double new_time)
void	SSPRK3Step (double current_time, double new_time, unsigned int n_stages=4)
void	computeLagrangianForce (double data_time)
void	computeLagrangianForce (libMesh::PetscVector< double > &F_vec, libMesh::PetscVector< double > &X_vec, libMesh::PetscVector< double > &U_vec, libMesh::PetscVector< double > *P_vec, double data_time, unsigned int part)
void	putToDatabase (SAMRAI::tbox::Pointer< SAMRAI::tbox::Database > db) override

Protected Member Functions
void	doInitializeFEEquationSystems () override
void	doInitializeFESystemVectors () override
void	doInitializeFEData (bool use_present_data) override
void	doForwardEulerStep (libMesh::PetscVector< double > &X_new_vec, libMesh::PetscVector< double > &U_new_vec, libMesh::PetscVector< double > *P_new_vec, libMesh::PetscVector< double > &X_current_vec, libMesh::PetscVector< double > &U_current_vec, libMesh::PetscVector< double > *P_current_vec, libMesh::PetscVector< double > &F_current_vec, libMesh::PetscVector< double > *dP_dt_current_vec, double current_time, double new_time, unsigned int part)

Protected Attributes
std::vector< double >	d_rhos
	Structure mass densities.
std::vector< double >	d_etas
	Structure damping coefficients.

Detailed Description

Class FEMechanicsExplicitIntegrator is an implementation of the abstract base class FEMechanicsBase that provides a simple explicit elastodynamics time integrator with an interface that is similar to IBFEMethod to facilitate model re-use.

See also

IBFEMethod

Member Function Documentation

backwardEulerStep()

void IBAMR::FEMechanicsExplicitIntegrator::backwardEulerStep	(	double	current_time,
		double	new_time
	)

Advance the structural velocities and positions using backward Euler.

NOTE: This is not a true backward Euler method; we simply use the most recent approximations to the updated velocity and position to compute the force at the end of the time step, and then use that force to increment the velocity and position via backward Euler.

computeLagrangianForce() [1/2]

void IBAMR::FEMechanicsExplicitIntegrator::computeLagrangianForce

(

double

data_time

)

Compute the Lagrangian force at the specified time within the current time interval.

computeLagrangianForce() [2/2]

void IBAMR::FEMechanicsExplicitIntegrator::computeLagrangianForce	(	libMesh::PetscVector< double > &	F_vec,
		libMesh::PetscVector< double > &	X_vec,
		libMesh::PetscVector< double > &	U_vec,
		libMesh::PetscVector< double > *	P_vec,
		double	data_time,
		unsigned int	part
	)

Compute the Lagrangian force at the specified time within the current time interval using the provided data vectors.

doForwardEulerStep()

void IBAMR::FEMechanicsExplicitIntegrator::doForwardEulerStep ( libMesh::PetscVector< double > &  X_new_vec, libMesh::PetscVector< double > &  U_new_vec, libMesh::PetscVector< double > *  P_new_vec, libMesh::PetscVector< double > &  X_current_vec, libMesh::PetscVector< double > &  U_current_vec, libMesh::PetscVector< double > *  P_current_vec, libMesh::PetscVector< double > &  F_current_vec, libMesh::PetscVector< double > *  dP_dt_current_vec, double  current_time, double  new_time, unsigned int  part  )

protected

Perform a forward Euler step.

doInitializeFEData()

void IBAMR::FEMechanicsExplicitIntegrator::doInitializeFEData ( bool  use_present_data )

overrideprotected

Do the actual work in reinitializeFEData and initializeFEData. if use_present_data is true then the current content of the solution vectors is used: more exactly, the coordinates and velocities (computed by initializeCoordinates and initializeVelocity) are considered as being up to date, as is the direct forcing kinematic data.

doInitializeFEEquationSystems()

void IBAMR::FEMechanicsExplicitIntegrator::doInitializeFEEquationSystems ( )

overrideprotected

Do the actual work in initializeFEEquationSystems.

doInitializeFESystemVectors()

void IBAMR::FEMechanicsExplicitIntegrator::doInitializeFESystemVectors ( )

overrideprotected

Do the actual work of setting up libMesh system vectors.

forwardEulerStep()

void IBAMR::FEMechanicsExplicitIntegrator::forwardEulerStep	(	double	current_time,
		double	new_time
	)

Advance the structural velocities and positions using forward Euler.

midpointStep()

void IBAMR::FEMechanicsExplicitIntegrator::midpointStep	(	double	current_time,
		double	new_time
	)

Advance the structural velocities and positions using the explicit midpoint rule.

modifiedEulerStep()

void IBAMR::FEMechanicsExplicitIntegrator::modifiedEulerStep	(	double	current_time,
		double	new_time
	)

Advance the structural velocities and positions using "modified" Euler.

NOTE: This scheme first advances the velocity using forward Euler, and then uses the updated velocity to advance the position of the structure.

modifiedTrapezoidalStep()

void IBAMR::FEMechanicsExplicitIntegrator::modifiedTrapezoidalStep	(	double	current_time,
		double	new_time
	)

Advance the structural velocities and positions using a modified explicit trapezoidal rule.

NOTE: In this scheme, the first stage uses a modified Euler scheme (

See also

modifiedEulerStep), and the second stage uses a modified explicit trapezoidal rule, in which the final approximation to the updated velocity is used instead of the intermediate updated approximation used in the standard SSP RK2 scheme.

postprocessIntegrateData()

void IBAMR::FEMechanicsExplicitIntegrator::postprocessIntegrateData ( double  current_time, double  new_time, int  num_cycles  )

override

Method to clean up data following call(s) to integrateHierarchy().

preprocessIntegrateData()

void IBAMR::FEMechanicsExplicitIntegrator::preprocessIntegrateData ( double  current_time, double  new_time, int  num_cycles  )

override

Method to prepare to advance data from current_time to new_time.

putToDatabase()

void IBAMR::FEMechanicsExplicitIntegrator::putToDatabase ( SAMRAI::tbox::Pointer< SAMRAI::tbox::Database >  db )

override

Write out object state to the given database.

SSPRK3Step()

void IBAMR::FEMechanicsExplicitIntegrator::SSPRK3Step	(	double	current_time,
		double	new_time,
		unsigned int	n_stages = 4
	)

Advance the structural velocities and positions using the explicit SSP RK3 scheme.

The implementation supports either 3- or 4-stage variants. The default is the 4-stage version, which has a larger stability region.

trapezoidalStep()

void IBAMR::FEMechanicsExplicitIntegrator::trapezoidalStep	(	double	current_time,
		double	new_time
	)

Advance the structural velocities and positions using the explicit SSP RK2 scheme, which is the explicit trapezoidal rule.

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

• /home/runner/work/IBAMR/IBAMR/include/ibamr/FEMechanicsExplicitIntegrator.h
• /home/runner/work/IBAMR/IBAMR/src/IB/FEMechanicsExplicitIntegrator.cpp