Description

An implicit form of the ChMatterPeriBBimplicit material, where instead of tangent stiffness matrices we use a compliant-constraint formulation.

Moreover, this adds the ability of having two stages for breaking: an intermediate fractured state where bonds are still in place but unilateral, and a fully broken state where bonds are removed. Simple bond-based peridynamic material whose elasticity depends on a single parameter, that is K, the bulk modulus.
The Poisson ratio is always 1/4 and cannot be set otherwise, as in general for bond-based elasticity models. Having a fixed Poisson ration can be a limitation, but the positive note is that this material is computationally-efficient.

#include <ChMatterPeriBBimplicit.h>

Inheritance diagram for chrono::peridynamics::ChMatterPeriBBimplicit:

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Collaboration diagram for chrono::peridynamics::ChMatterPeriBBimplicit:

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Public Member Functions
void	SetYoungModulus (double mE)
	Set the material Young modulus. More...

double	VolumeCorrection (double dist, double horizon, double vol_size)
	When doing quadrature, particle volumes that overlap with the horizon should be scaled proportionally to how much of their volume is really inside the horizon sphere. More...

virtual void	ComputeForces ()
	CONSTITUTIVE MODEL - INTERFACE TO IMPLEMENT: IMPORTANT Add the forces caused by this material to the ChNodePeri::F vector of each ChNodePeri. More...

virtual void	Setup () override
	CONSTITUTIVE MODEL - INTERFACE TO IMPLEMENT: (optionally) This function is called at each time step. More...

virtual unsigned int	GetNumConstraints () override
	Get the number of scalar constraints (maybe used for implicit materials)

virtual void	IntLoadResidual_CqL (const unsigned int off_L, ChVectorDynamic<> &R, const ChVectorDynamic<> &L, const double c) override

virtual void	IntLoadConstraint_C (const unsigned int off, ChVectorDynamic<> &Qc, const double c, bool do_clamp, double recovery_clamp) override
	Takes the term C, scale and adds to Qc at given offset: Qc += c*C. More...

virtual void	InjectConstraints (ChSystemDescriptor &descriptor) override
	Register with the given system descriptor any ChConstraint objects associated with this item.

virtual void	LoadConstraintJacobians () override
	Compute and load current Jacobians in encapsulated ChConstraint objects.

virtual void	IntToDescriptor (const unsigned int off_v, const ChStateDelta &v, const ChVectorDynamic<> &R, const unsigned int off_L, const ChVectorDynamic<> &L, const ChVectorDynamic<> &Qc)

virtual void	IntFromDescriptor (const unsigned int off_v, ChStateDelta &v, const unsigned int off_L, ChVectorDynamic<> &L)

Public Member Functions inherited from chrono::peridynamics::ChMatterPeri< ChMatterDataPerNode, ChMatterDataPerBondBBimplicit >
	ChMatterPeri ()
	Build a cluster of nodes for peridynamics. More...

	ChMatterPeri (const ChMatterPeri &other)

unsigned int	GetNnodes () const
	Get the number of nodes.

unsigned int	GetNbonds () const
	Get the number of bonds.

const std::unordered_map< ChNodePeri *, ChMatterDataPerNode > &	GetMapOfNodes ()
	Access the node container.

std::unordered_map< std::pair< ChNodePeri , ChNodePeri >, ChMatterDataPerBondBBimplicit > &	GetMapOfBonds ()
	Access the bonds container.

virtual std::shared_ptr< ChNodePeri >	AddNode (std::shared_ptr< ChNodePeri > mnode) override
	Add a node to the particle cluster.

virtual bool	RemoveNode (std::shared_ptr< ChNodePeri > mnode) override
	Remove a node from the particle cluster.

virtual bool	AddProximity (ChNodePeri nodeA, ChNodePeri nodeB) override
	Add a proximity: this will be called thousand of times by the broadphase collision detection. More...

virtual void	ComputeForcesReset () override
	CONSTITUTIVE MODEL - INTERFACE TO IMPLEMENT: (optionally) Base behaviour: More...

virtual void	ComputeCollisionStateChanges () override
	CONSTITUTIVE MODEL - INTERFACE TO IMPLEMENT: (optionally) Changes the collision model of nodes, from collision to no collision, etc., ex when an interface is generated, depending on the evolution of the system. More...

void	SetContactMaterial (const std::shared_ptr< ChContactMaterial > &mnewsurf)
	Set the material surface for 'boundary contact'.

std::shared_ptr< ChContactMaterial > &	GetContactMaterial ()
	Set the material surface for 'boundary contact'.

virtual void	ArchiveOut (ChArchiveOut &marchive)
	Method to allow serialization of transient data to archives.

virtual void	ArchiveIn (ChArchiveIn &marchive)
	Method to allow de-serialization of transient data from archives.

Public Member Functions inherited from chrono::peridynamics::ChMatterPeriBase
virtual void	SetupInitial ()
	CONSTITUTIVE MODEL - INTERFACE TO IMPLEMENT: (optionally) This function is called where system construction is completed, at the beginning of the simulation. More...

ChPeridynamics *	GetContainer () const

void	SetContainer (ChPeridynamics *mc)

Public Attributes
double	k_bulk = 100
	bulk modulus, unit Pa, i.e. N/m^2

double	damping = 0.001
	damping, as Rayleigh beta (bulk stiffness-proportional)

double	max_stretch_fracture = 1e30
	maximum stretch for fracure - after this, bonds will become unilateral. Default no break.

double	max_stretch_break = 1e30
	maximum stretch for full breaking - after this, bonds will break. Default no break.

Additional Inherited Members
Protected Attributes inherited from chrono::peridynamics::ChMatterPeri< ChMatterDataPerNode, ChMatterDataPerBondBBimplicit >
std::unordered_map< ChNodePeri *, ChMatterDataPerNode >	nodes
	nodes

std::unordered_map< std::pair< ChNodePeri , ChNodePeri >, ChMatterDataPerBondBBimplicit >	bonds
	bonds

std::shared_ptr< ChContactMaterial >	matsurface
	data for surface contact and impact

Protected Attributes inherited from chrono::peridynamics::ChMatterPeriBase
ChPeridynamics *	container = 0

Member Function Documentation

◆ ComputeForces()

virtual void chrono::peridynamics::ChMatterPeriBBimplicit::ComputeForces ( )

inlinevirtual

CONSTITUTIVE MODEL - INTERFACE TO IMPLEMENT: IMPORTANT Add the forces caused by this material to the ChNodePeri::F vector of each ChNodePeri.

Child class can use the containers this->nodes and this->bonds to compute F, assuming bonds have been updated with latest collision detection.

Implements chrono::peridynamics::ChMatterPeriBase.

◆ IntLoadConstraint_C()

virtual void chrono::peridynamics::ChMatterPeriBBimplicit::IntLoadConstraint_C	(	const unsigned int	off,
		ChVectorDynamic<> &	Qc,
		const double	c,
		bool	do_clamp,
		double	recovery_clamp
	)

inlineoverridevirtual

Takes the term C, scale and adds to Qc at given offset: Qc += c*C.

Parameters

off	offset in Qc residual
Qc	result: the Qc residual, Qc += c*C
c	a scaling factor
do_clamp	apply clamping to c*C?
recovery_clamp	value for min/max clamping of c*C

Reimplemented from chrono::peridynamics::ChMatterPeriBase.

◆ IntLoadResidual_CqL()

virtual void chrono::peridynamics::ChMatterPeriBBimplicit::IntLoadResidual_CqL	(	const unsigned int	off_L,
		ChVectorDynamic<> &	R,
		const ChVectorDynamic<> &	L,
		const double	c
	)

inlineoverridevirtual

Parameters

off_L	offset in L multipliers
R	result: the R residual, R += cCq'L
L	the L vector
c	a scaling factor

Reimplemented from chrono::peridynamics::ChMatterPeriBase.

◆ Setup()

virtual void chrono::peridynamics::ChMatterPeriBBimplicit::Setup ( )

inlineoverridevirtual

CONSTITUTIVE MODEL - INTERFACE TO IMPLEMENT: (optionally) This function is called at each time step.

Maybe your constitutive law has to initialize some state data, if so you can implement this function, otherwise leave as empty.

Reimplemented from chrono::peridynamics::ChMatterPeriBase.

◆ SetYoungModulus()

void chrono::peridynamics::ChMatterPeriBBimplicit::SetYoungModulus ( double mE )

inline

Set the material Young modulus.

The unique bulk modulus will be automatically computed, since in this material Poisson is always =1/4

◆ VolumeCorrection()

double chrono::peridynamics::ChMatterPeriBBimplicit::VolumeCorrection	(	double	dist,
		double	horizon,
		double	vol_size
	)

inline

When doing quadrature, particle volumes that overlap with the horizon should be scaled proportionally to how much of their volume is really inside the horizon sphere.

A simple and very often used approximation is the following 'fading' function.

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

/builds/uwsbel/chrono/src/chrono_peridynamics/ChMatterPeriBBimplicit.h

Description

Public Member Functions

Public Attributes

Additional Inherited Members

Member Function Documentation

◆ ComputeForces()

◆ IntLoadConstraint_C()

◆ IntLoadResidual_CqL()

◆ Setup()

◆ SetYoungModulus()

◆ VolumeCorrection()