Description

Physical system for fluid-solid interaction problems.

This class is used to represent fluid-solid interaction problems consisting of fluid dynamics and multibody system. Each of the two underlying physics is an independent object owned and instantiated by this class. The FSI system owns other objects to handle the interface between the two systems, boundary condition enforcing markers, and data.

#include <ChSystemFsi.h>

Classes
struct	ElasticMaterialProperties
	Structure with elastic material properties. More...

Public Types
enum	OutpuMode { OutpuMode::CSV, OutpuMode::CHPF, OutpuMode::NONE }
	Output mode. More...

Public Member Functions
	ChSystemFsi (ChSystem &other_physicalSystem)
	Constructor for FSI system.

	~ChSystemFsi ()
	Destructor for the FSI system.

void	DoStepDynamics_FSI ()
	Function to integrate the FSI system in time. More...

void	DoStepDynamics_ChronoRK2 ()
	Function to integrate the multibody system dynamics based on Runge-Kutta 2nd-order integration scheme.

void	SetVerbose (bool m_verbose)
	Enable/disable m_verbose terminal output.

void	ReadParametersFromFile (const std::string &json_file)
	Read Chrono::FSI parameters from the specified JSON file.

void	SetInitialSpacing (double spacing)
	Set initial spacing.

void	SetKernelLength (double length)
	Set SPH kernel length.

void	SetContainerDim (const ChVector<> &boxDim)
	Set the fluid container dimension.

void	SetBoundaries (const ChVector<> &cMin, const ChVector<> &cMax)
	Set periodic boundary condition for fluid.

void	SetNumBoundaryLayers (int num_layers)
	Set number of boundary layers (default: 3).

void	SetDensity (double rho0)
	Set (initial) density.

void	SetInitPressure (const double fzDim)
	Set prescribed initial pressure for gravity field.

void	Set_G_acc (const ChVector<> &gravity)
	Set gravity for the FSI syatem.

void	SetBodyForce (const ChVector<> &force)
	Set a constant force applied to the fluid. More...

void	SetStepSize (double dT, double dT_Flex=0)
	Set FSI integration step size.

void	SetMaxStepSize (double dT_max)
	Set the maximum allowable integration step size.

void	SetAdaptiveTimeStepping (bool adaptive)
	Enable/disable adaptive time stepping.

void	SetDiscreType (bool useGmatrix, bool useLmatrix)
	Set SPH discretization type, consistent or inconsistent.

void	SetWallBC (BceVersion wallBC)
	Set wall boundary condition.

void	SetSPHLinearSolver (SolverType lin_solver)
	Set the linear system solver for implicit methods.

void	SetSPHMethod (FluidDynamics SPH_method, SolverType lin_solver=SolverType::BICGSTAB)
	Set the SPH method and, optionally, the linear solver type.

void	SetElasticSPH (const ElasticMaterialProperties mat_props)
	Enable solution of elastic SPH (for continuum representation of granular dynamics). More...

void	SetOutputDirectory (const std::string &output_dir)
	Set output directory for FSI data. More...

void	SetOutputLength (int OutputLength)
	Set simulation data output length.

void	SetParticleOutputMode (OutpuMode mode)
	Set the FSI system output mode (default: NONE).

double	GetKernelLength () const
	Return the SPH kernel length of kernel function.

double	GetInitialSpacing () const
	Return the initial spacing of the SPH particles.

ChVector	GetContainerDim () const
	Set the fluid container dimension.

double	GetDensity () const
	Return density.

double	GetViscosity () const
	Return viscosity.

double	GetParticleMass () const
	Return SPH particle mass.

double	GetBasePressure () const
	Return base pressure.

ChVector	Get_G_acc () const
	Return gravitational acceleration.

double	GetSoundSpeed () const
	Return the speed of sound in the fluid phase.

ChVector	GetBodyForce () const
	Return the constant force applied to the fluid (if any).

double	GetStepSize () const
	Return the FSI integration step size.

double	GetMaxStepSize () const
	Return the current value of the maximum allowable integration step size.

bool	GetAdaptiveTimeStepping () const
	Return a flag inicating whether adaptive time stepping is enabled.

size_t	GetNumFluidMarkers () const
	Get the current number of fluid SPH particles.

size_t	GetNumBoundaryMarkers () const
	Get the current number of boundary BCE markers.

size_t	GetNumRigidBodyMarkers () const
	Get the current number of rigid body BCE markers.

size_t	GetNumFlexBodyMarkers () const
	Get the current number of flexible body BCE markers.

double	GetSimTime () const
	Get current simulation time.

std::vector< ChVector<> >	GetParticlePosOrProperties ()
	Return the SPH particle position.

std::vector< ChVector<> >	GetParticleVel ()
	Return the SPH particle velocity.

std::vector< std::shared_ptr< ChBody > > &	GetFsiBodies ()
	Get a reference to the FSI bodies. More...

std::shared_ptr< fea::ChMesh >	GetFsiMesh ()
	Return the FSI mesh for flexible elements.

std::vector< std::shared_ptr< fea::ChElementCableANCF > > &	GetFsiCables ()
	Get a reference to the FSI ChElementCableANCF. More...

std::vector< std::shared_ptr< fea::ChElementShellANCF_3423 > > &	GetFsiShells ()
	Get a reference to the FSI ChElementShellANCF_3423. More...

std::vector< std::shared_ptr< fea::ChNodeFEAxyzD > > &	GetFsiNodes ()
	Get a reference to the FSI ChNodeFEAxyzD. More...

void	AddFsiBody (std::shared_ptr< ChBody > mbody)
	Add FSI body to the FsiSystem.

void	SetCableElementsNodes (std::vector< std::vector< int >> elementsNodes)
	Set number of nodes in FEA cable elements in the FSI system.

void	SetShellElementsNodes (std::vector< std::vector< int >> elementsNodes)
	Set number of nodes in FEA shell elements in the FSI system.

void	SetFsiMesh (std::shared_ptr< fea::ChMesh > other_fsi_mesh)
	Set the FSI mesh for flexible elements.

void	Initialize ()
	Complete construction of the FSI system (fluid and BDE objects). More...

void	WriteParticleFile (const std::string &outfilename) const
	Write FSI system particle output.

void	PrintParticleToFile (const std::string &dir) const
	Save the SPH particle information into files. More...

void	AddSPHParticle (const ChVector<> &point, double rho0, double pres0, double mu0, double h, const ChVector<> &velocity=ChVector<>(0), const ChVector<> &tauXxYyZz=ChVector<>(0), const ChVector<> &tauXyXzYz=ChVector<>(0))
	Add an SPH particle with given properties to the FSI system.

void	AddSPHParticle (const ChVector<> &point, const ChVector<> &velocity=ChVector<>(0), const ChVector<> &tauXxYyZz=ChVector<>(0), const ChVector<> &tauXyXzYz=ChVector<>(0))
	Add an SPH particle with current properties to the SPH system.

void	AddBoxSPH (double initSpace, double kernelLength, const ChVector<> &boxCenter, const ChVector<> &boxHalfDim)
	Create SPH particles in the specified box volume. More...

void	AddBoxBCE (std::shared_ptr< ChBody > body, const ChVector<> &relPos, const ChQuaternion<> &relRot, const ChVector<> &size, int plane=12, bool isSolid=false)
	Add BCE markers in a box of given dimensions and at given position associated with the specified body.

void	AddSphereBCE (std::shared_ptr< ChBody > body, const ChVector<> &relPos, const ChQuaternion<> &relRot, double radius)
	Add BCE markers in a sphere of given radius associated with the specified body.

void	AddSphereSurfaceBCE (std::shared_ptr< ChBody > body, const ChVector<> &relPos, const ChQuaternion<> &relRot, double radius, double kernel_h)
	Add BCE markers on a spherical surface of given radius associated with the specified body.

void	AddCylinderBCE (std::shared_ptr< ChBody > body, const ChVector<> &relPos, const ChQuaternion<> &relRot, double radius, double height, double kernel_h, bool cartesian=true)
	Add BCE markers in a cylinder of given dimensions and at given position associated with the specified body.

void	AddCylinderSurfaceBCE (std::shared_ptr< ChBody > body, const ChVector<> &relPos, const ChQuaternion<> &relRot, double radius, double height, double kernel_h)
	Add BCE markers on a cylindrical surface of given dimensions and at given position associated with the specified body.

void	AddConeBCE (std::shared_ptr< ChBody > body, const ChVector<> &relPos, const ChQuaternion<> &relRot, double radius, double height, double kernel_h, bool cartesian=true)
	Add BCE markers in a cone of given dimensions and at given position associated with the specified body.

void	AddPointsBCE (std::shared_ptr< ChBody > body, const std::vector< ChVector<>> &points, const ChVector<> &collisionShapeRelativePos, const ChQuaternion<> &collisionShapeRelativeRot)
	Add BCE markers from a set of points and associate them with the given body.

void	AddFileBCE (std::shared_ptr< ChBody > body, const std::string &dataPath, const ChVector<> &collisionShapeRelativePos, const ChQuaternion<> &collisionShapeRelativeRot, double scale, bool isSolid=true)
	Add BCE markers read from the specified file andd associate them with the given body.

void	AddFEAmeshBCE (std::shared_ptr< fea::ChMesh > my_mesh, const std::vector< std::vector< int >> &NodeNeighborElement, const std::vector< std::vector< int >> &_1D_elementsNodes, const std::vector< std::vector< int >> &_2D_elementsNodes, bool add1DElem, bool add2DElem, bool multiLayer, bool removeMiddleLayer, int SIDE, int SIZE2D)
	Add BCE markers from mesh.

void	AddANCFshellBCE (std::vector< std::shared_ptr< fea::ChElementShellANCF_3423 >> &m_fsi_shells, std::shared_ptr< fea::ChMesh > mesh, bool multiLayer=true, bool removeMiddleLayer=false, int SIDE=-2)
	Add BCE markers genetrated from ANCF shell elements.

void	AddANCFshellBCE (std::vector< std::shared_ptr< fea::ChElementShellANCF_3423 >> &m_fsi_shells, std::vector< std::shared_ptr< fea::ChNodeFEAxyzD >> &m_fsi_nodes, std::shared_ptr< fea::ChMesh > mesh, const std::vector< std::vector< int >> &elementsNodes, const std::vector< std::vector< int >> &NodeNeighborElement, bool multiLayer=true, bool removeMiddleLayer=false, int SIDE=-2)
	Add BCE markers genetrated from shell elements.

void	AddSphereBody (std::shared_ptr< ChMaterialSurface > mat_prop, double density, const ChVector<> &pos, double radius)
	Create and add to the FSI system a rigid body with spherical shape. More...

void	AddCylinderBody (std::shared_ptr< ChMaterialSurface > mat_prop, double density, const ChVector<> &pos, const ChQuaternion<> &rot, double radius, double length)
	Create and add to the FSI system a rigid body with cylindrical shape. More...

void	AddBoxBody (std::shared_ptr< ChMaterialSurface > mat_prop, double density, const ChVector<> &pos, const ChQuaternion<> &rot, const ChVector<> &hsize)
	Create and add to the FSI system a rigid body with box shape. More...

Static Public Member Functions
static void	CreateMeshPoints (std::shared_ptr< geometry::ChTriangleMeshConnected > mesh, double delta, std::vector< ChVector<>> &point_cloud)
	Utility function for creating points filling a closed mesh. More...

Friends
class	ChVisualizationFsi

Member Enumeration Documentation

◆ OutpuMode

enum chrono::fsi::ChSystemFsi::OutpuMode

strong

Output mode.

Enumerator
CSV	comma-separated value
CHPF	binary
NONE	none

Member Function Documentation

◆ AddBoxBody()

void chrono::fsi::ChSystemFsi::AddBoxBody	(	std::shared_ptr< ChMaterialSurface >	mat_prop,
		double	density,
		const ChVector<> &	pos,
		const ChQuaternion<> &	rot,
		const ChVector<> &	hsize
	)

Create and add to the FSI system a rigid body with box shape.

BCE markers are created in the entire box volume using the current spacing value.

◆ AddBoxSPH()

void chrono::fsi::ChSystemFsi::AddBoxSPH	(	double	initSpace,
		double	kernelLength,
		const ChVector<> &	boxCenter,
		const ChVector<> &	boxHalfDim
	)

Create SPH particles in the specified box volume.

The SPH particles are created on a uniform grid with given spacing.

◆ AddCylinderBody()

void chrono::fsi::ChSystemFsi::AddCylinderBody	(	std::shared_ptr< ChMaterialSurface >	mat_prop,
		double	density,
		const ChVector<> &	pos,
		const ChQuaternion<> &	rot,
		double	radius,
		double	length
	)

Create and add to the FSI system a rigid body with cylindrical shape.

BCE markers are created in the entire cylindrical volume using the current spacing value.

◆ AddSphereBody()

void chrono::fsi::ChSystemFsi::AddSphereBody	(	std::shared_ptr< ChMaterialSurface >	mat_prop,
		double	density,
		const ChVector<> &	pos,
		double	radius
	)

Create and add to the FSI system a rigid body with spherical shape.

BCE markers are created in the entire spherical volume using the current spacing value.

◆ CreateMeshPoints()

void chrono::fsi::ChSystemFsi::CreateMeshPoints	(	std::shared_ptr< geometry::ChTriangleMeshConnected >	mesh,
		double	delta,
		std::vector< ChVector<>> &	point_cloud
	)

static

Utility function for creating points filling a closed mesh.

Calculate uu parameter and test bound

ray intersection

◆ DoStepDynamics_FSI()

void chrono::fsi::ChSystemFsi::DoStepDynamics_FSI ( )

Function to integrate the FSI system in time.

It uses a Runge-Kutta 2nd order algorithm to update both the fluid and multibody system dynamics. The midpoint data of MBS is needed for fluid dynamics update.

◆ GetFsiBodies()

std::vector<std::shared_ptr<ChBody> >& chrono::fsi::ChSystemFsi::GetFsiBodies ( )

inline

Get a reference to the FSI bodies.

FSI bodies are the ones seen by the fluid dynamics system.

◆ GetFsiCables()

std::vector<std::shared_ptr<fea::ChElementCableANCF> >& chrono::fsi::ChSystemFsi::GetFsiCables ( )

inline

Get a reference to the FSI ChElementCableANCF.

FSI ChElementCableANCF are the ones seen by the fluid dynamics system.

◆ GetFsiNodes()

std::vector<std::shared_ptr<fea::ChNodeFEAxyzD> >& chrono::fsi::ChSystemFsi::GetFsiNodes ( )

inline

Get a reference to the FSI ChNodeFEAxyzD.

FSI ChNodeFEAxyzD are the ones seen by the fluid dynamics system.

◆ GetFsiShells()

std::vector<std::shared_ptr<fea::ChElementShellANCF_3423> >& chrono::fsi::ChSystemFsi::GetFsiShells ( )

inline

Get a reference to the FSI ChElementShellANCF_3423.

FSI ChElementShellANCF_3423 are the ones seen by the fluid dynamics system.

◆ Initialize()

void chrono::fsi::ChSystemFsi::Initialize ( )

Complete construction of the FSI system (fluid and BDE objects).

Use parameters read from JSON file and/or specified through various Set functions.

◆ PrintParticleToFile()

void chrono::fsi::ChSystemFsi::PrintParticleToFile ( const std::string & dir ) const

Save the SPH particle information into files.

This function creates three CSV files for SPH particles, boundary BCE markers, and solid BCE markers data.

◆ SetBodyForce()

void chrono::fsi::ChSystemFsi::SetBodyForce ( const ChVector<> & force )

Set a constant force applied to the fluid.

Solid bodies are not explicitly affected by this force, but they are affected indirectly through the fluid.

◆ SetElasticSPH()

void chrono::fsi::ChSystemFsi::SetElasticSPH ( const ElasticMaterialProperties mat_props )

Enable solution of elastic SPH (for continuum representation of granular dynamics).

By default, a ChSystemFSI solves an SPH fluid dynamics problem.

◆ SetOutputDirectory()

void chrono::fsi::ChSystemFsi::SetOutputDirectory ( const std::string & output_dir )

Set output directory for FSI data.

No output is generated by default (for better performance). If an output directory is specified, output files with information on each FSI body and node are generated in a subdirectory 'fsi/' of the given output directory. It is the caller's responsibility to ensure that output_dir exists.

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

/builds/uwsbel/chrono/src/chrono_fsi/ChSystemFsi.h
/builds/uwsbel/chrono/src/chrono_fsi/ChSystemFsi.cpp

Description

Classes

Public Types

Public Member Functions

Static Public Member Functions

Friends

Member Enumeration Documentation

◆ OutpuMode

Member Function Documentation

◆ AddBoxBody()

◆ AddBoxSPH()

◆ AddCylinderBody()

◆ AddSphereBody()

◆ CreateMeshPoints()

◆ DoStepDynamics_FSI()

◆ GetFsiBodies()

◆ GetFsiCables()

◆ GetFsiNodes()

◆ GetFsiShells()

◆ Initialize()

◆ PrintParticleToFile()

◆ SetBodyForce()

◆ SetElasticSPH()

◆ SetOutputDirectory()