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LinearPlasticViscoelasticInteraction Class Reference

Computes normal forces in case of a linear plastic visco-elastic interaction. More...

#include <LinearPlasticViscoelasticInteraction.h>

+ Inheritance diagram for LinearPlasticViscoelasticInteraction:

Public Types

typedef
LinearPlasticViscoelasticNormalSpecies 
SpeciesType
 An alias for the species (needed for e.g. ThermalSpecies) More...
 

Public Member Functions

 LinearPlasticViscoelasticInteraction (BaseInteractable *P, BaseInteractable *I, Mdouble timeStamp)
 Constructor. More...
 
 LinearPlasticViscoelasticInteraction (const LinearPlasticViscoelasticInteraction &p)
 Copy constructor. More...
 
virtual ~LinearPlasticViscoelasticInteraction ()
 Destructor. More...
 
void computeLinearPlasticViscoelasticForce ()
 Creates a copy of an object of this class. (Deep copy) More...
 
void computeNormalForce ()
 Calls computeLinearPlasticViscoElasticForce(). More...
 
virtual void read (std::istream &is)
 Interaction read function, which accepts an std::istream as input. More...
 
virtual void write (std::ostream &os) const
 Interaction write function, which accepts an std::ostream as input. More...
 
virtual std::string getBaseName () const
 Returns the name of the interaction. More...
 
Mdouble getElasticEnergy () const
 Computes and returns the amount of elastic energy stored in the spring. More...
 
const
LinearPlasticViscoelasticNormalSpecies
getSpecies () const
 
Mdouble getMaxOverlap () const
 
void setMaxOverlap (const Mdouble maxOverlap)
 
Mdouble getUnloadingStiffness () const
 
- Public Member Functions inherited from BaseInteraction
 BaseInteraction (BaseInteractable *P, BaseInteractable *I, Mdouble timeStamp)
 A constructor takes the BaseInteractable objects which are interacting (come into contact) and time the interaction starts. More...
 
 BaseInteraction (const BaseInteraction &p)
 Copy constructor. More...
 
 BaseInteraction ()
 Empty constructor. More...
 
virtual ~BaseInteraction ()
 The default destructor. More...
 
virtual void actionsOnErase ()
 If an interaction needs to do something before it gets erased, add it here. E.g. Liquid bridges rupture at the end of their lifetime, and the liquid bridge volume has to be redistributed. The reason this action is not done in the destructor is that this action should not be taken when erasing ghost interactions. More...
 
virtual void computeForce ()
 Virtual function that contains the force law between the two objects interacting. More...
 
void writeToFStat (std::ostream &os) const
 Writes forces data to the FStat file. More...
 
virtual std::string getName () const
 Virtual function which allows interactions to be named. More...
 
void setDistance (Mdouble distance)
 Sets the interaction distance between the two interacting objects. More...
 
void setNormal (Vec3D normal)
 Sets the normal vector between the two interacting objects. More...
 
void setOverlap (Mdouble overlap)
 Set the overlap between the two interacting object. More...
 
void setContactPoint (Vec3D contactPoint)
 Set the location of the contact point between the two interacting objects. More...
 
void setTimeStamp (Mdouble timeStamp)
 Updates the time step of the interacting. Note, timesteps used to find completed interactions. More...
 
void setSpecies (BaseSpecies *species)
 Set the Species of the interaction; note this can either be a Species or MixedSpecies. More...
 
void setP (BaseInteractable *P)
 Sets the first object involved in the interaction (normally a particle). More...
 
void setI (BaseInteractable *I)
 Sets the second object involved in the interaction (often particle or wall). More...
 
void setHandler (InteractionHandler *handler)
 Sets the pointer to the interaction hander which is storing this interaction. More...
 
InteractionHandlergetHandler () const
 Gets a point to the interaction handlers to which this interaction belongs. More...
 
const Vec3DgetForce () const
 Gets the current force (vector) between the two interacting objects. More...
 
const Vec3DgetTorque () const
 Gets the current torque (vector) between the two interacting objects. More...
 
const Vec3DgetNormal () const
 Gets the normal vector between the two interacting objects. More...
 
const Vec3DgetContactPoint () const
 Gets constant reference to contact point (vector). More...
 
Mdouble getOverlap () const
 Returns a Mdouble with the current overlap between the two interacting objects. More...
 
Mdouble getContactRadius () const
 Returns a Mdouble with the current contact between the two interacting objects. More...
 
void removeFromHandler ()
 Removes this interaction from its interaction hander. More...
 
void copySwitchPointer (const BaseInteractable *original, BaseInteractable *ghost) const
 This copies the interactions of the original particle and replaces the original with the ghost copy. More...
 
void gatherContactStatistics ()
 
BaseInteractablegetP ()
 Returns a pointer to first object involved in the interaction (normally a particle). More...
 
BaseInteractablegetI ()
 
const BaseInteractablegetP () const
 
const BaseInteractablegetI () const
 Returns a constant pointer to the second object involved in the interaction. More...
 
Mdouble getTimeStamp () const
 Returns an Mdouble which is the time stamp of the interaction. More...
 
virtual void integrate (Mdouble timeStep)
 integrates variables of the interaction which need to be integrate e.g. the tangential overlap. More...
 
virtual Mdouble getTangentialOverlap () const
 get the length of the current tangential overlap More...
 
Mdouble getDistance () const
 Returns an Mdouble which is the norm (length) of distance vector. More...
 
const Vec3DgetRelativeVelocity () const
 Returns a constant reference to a vector of relative velocity. More...
 
Mdouble getNormalRelativeVelocity () const
 Returns a double which is the norm (length) of the relative velocity vector. More...
 
Mdouble getAbsoluteNormalForce () const
 Returns the absolute value of the norm (length) of the Normal force vector. More...
 
virtual BaseInteractioncopy () const =0
 Makes a copy of the interaction and returns a pointer to the copy. More...
 
unsigned int getMultiContactIdentifier () const
 
void setMultiContactIdentifier (unsigned int multiContactIdentifier_)
 
virtual void rotateHistory (Matrix3D &rotationMatrix)
 When periodic particles are used, some interactions need certain history properties rotated (e.g. tangential springs). This is the function for that. More...
 
virtual void actionsAfterTimeStep ()
 
virtual unsigned getNumberOfFieldsVTK () const
 
virtual std::string getTypeVTK (unsigned i) const
 
virtual std::string getNameVTK (unsigned i) const
 
virtual std::vector< MdoublegetFieldVTK (unsigned i) const
 
void setForce (Vec3D force)
 set total force (this is used by the normal force, tangential forces are added use addForce) More...
 
- Public Member Functions inherited from BaseObject
 BaseObject ()
 Default constructor. More...
 
 BaseObject (const BaseObject &p)
 Copy constructor, copies all the objects BaseObject contains. More...
 
virtual ~BaseObject ()
 virtual destructor More...
 
virtual void moveInHandler (const unsigned int index)
 Except that it is virtual, it does the same thing as setIndex() does. More...
 
void setIndex (const unsigned int index)
 Allows one to assign an index to an object in the handler/container. More...
 
void setId (const unsigned int id)
 Assigns a unique identifier to each object in the handler (container) which remains constant even after the object is deleted from the container/handler. More...
 
unsigned int getIndex () const
 Returns the index of the object in the handler. More...
 
unsigned int getId () const
 Returns the unique identifier of any particular object. More...
 

Private Attributes

Mdouble maxOverlap_
 

Additional Inherited Members

- Protected Member Functions inherited from BaseInteraction
virtual const Vec3D getTangentialForce () const
 
Mdouble getEffectiveRadius () const
 Returns a Mdouble to the effective radius of the interaction. (Not corrected for the overlap) More...
 
Mdouble getEffectiveMass () const
 Returns a Mdouble to the effective radius of the interaction. (Not corrected for the overlap) More...
 
Mdouble getEffectiveCorrectedRadius ()
 Returns a Mdouble to the effective radius corrected for the overlaps of the particles. More...
 
void addForce (Vec3D force)
 add an force increment to the total force. More...
 
void addTorque (Vec3D torque)
 
void setTorque (Vec3D torque)
 set the total force (this is used by the normal force, tangential torques are added use addTorque) More...
 
void setRelativeVelocity (Vec3D relativeVelocity)
 set the relative velocity of the current of the interactions. More...
 
void setNormalRelativeVelocity (Mdouble normalRelativeVelocit)
 set the normal component of the relative velocity. More...
 
void setAbsoluteNormalForce (Mdouble absoluteNormalForce)
 the absolute values of the norm (length) of the normal force More...
 
const BaseSpeciesgetBaseSpecies () const
 Return a constant point to BaseSpecies of the interaction. More...
 
virtual Mdouble getElasticEnergyAtEquilibrium (Mdouble adhesiveForce) const
 
virtual void reverseHistory ()
 When periodic particles some interaction need certain history properties reversing. This is the function for that. More...
 

Detailed Description

Computes normal forces in case of a linear plastic visco-elastic interaction.

Definition at line 36 of file LinearPlasticViscoelasticInteraction.h.

Member Typedef Documentation

Constructor & Destructor Documentation

LinearPlasticViscoelasticInteraction::LinearPlasticViscoelasticInteraction ( BaseInteractable P,
BaseInteractable I,
Mdouble  timeStamp 
)

Constructor.

Parameters
[in]P
[in]I
[in]timeStamp

Definition at line 39 of file LinearPlasticViscoelasticInteraction.cc.

References maxOverlap_.

40  : BaseInteraction(P, I, timeStamp)
41 {
42  maxOverlap_=0;
43 #ifdef DEBUG_CONSTRUCTOR
44  std::cout<<"LinearPlasticViscoelasticInteraction::LinearPlasticViscoelasticInteraction() finished"<<std::endl;
45 #endif
46 }
BaseInteraction()
Empty constructor.
LinearPlasticViscoelasticInteraction::LinearPlasticViscoelasticInteraction ( const LinearPlasticViscoelasticInteraction p)

Copy constructor.

Parameters
[in]p

Definition at line 50 of file LinearPlasticViscoelasticInteraction.cc.

References maxOverlap_.

51  : BaseInteraction(p)
52 {
54 #ifdef DEBUG_CONSTRUCTOR
55  std::cout<<"LinearPlasticViscoelasticInteraction::LinearPlasticViscoelasticInteraction(const LinearPlasticViscoelasticInteraction &p finished"<<std::endl;
56 #endif
57 }
BaseInteraction()
Empty constructor.
LinearPlasticViscoelasticInteraction::~LinearPlasticViscoelasticInteraction ( )
virtual

Destructor.

Definition at line 61 of file LinearPlasticViscoelasticInteraction.cc.

62 {
63 #ifdef DEBUG_DESTRUCTOR
64  std::cout<<"LinearPlasticViscoelasticInteraction::~LinearPlasticViscoelasticInteraction() finished"<<std::endl;
65 #endif
66 }

Member Function Documentation

void LinearPlasticViscoelasticInteraction::computeLinearPlasticViscoelasticForce ( )

Creates a copy of an object of this class. (Deep copy)

Computes the normal forces due to linear plastic visco elastic interaction.

Definition at line 96 of file LinearPlasticViscoelasticInteraction.cc.

References Vec3D::dot(), LinearPlasticViscoelasticNormalSpecies::getCohesionStiffness(), BaseInteraction::getContactPoint(), LinearPlasticViscoelasticNormalSpecies::getDissipation(), BaseInteraction::getEffectiveRadius(), BaseInteraction::getI(), LinearPlasticViscoelasticNormalSpecies::getLoadingStiffness(), getMaxOverlap(), BaseInteraction::getNormal(), BaseInteraction::getNormalRelativeVelocity(), BaseInteraction::getOverlap(), BaseInteraction::getP(), LinearPlasticViscoelasticNormalSpecies::getPenetrationDepthMax(), BaseInteraction::getRelativeVelocity(), getSpecies(), LinearPlasticViscoelasticNormalSpecies::getUnloadingStiffnessMax(), maxOverlap_, BaseInteraction::setAbsoluteNormalForce(), BaseInteraction::setForce(), setMaxOverlap(), BaseInteraction::setNormalRelativeVelocity(), BaseInteraction::setRelativeVelocity(), and BaseInteraction::setTorque().

Referenced by computeNormalForce().

97 {
98  // Compute the relative velocity vector of particle P w.r.t. I
99  setRelativeVelocity(getP()->getVelocityAtContact(getContactPoint()) - getI()->getVelocityAtContact(getContactPoint()));
100  // Compute the projection of vrel onto the normal (can be negative)
102 
103  if (getOverlap() > 0) //if contact forces
104  {
106 
107  //calculate the overlap above which the max. unloading stiffness becomes active (the 'fluid branch')
108  Mdouble effectiveDiameter = 2.0 * getEffectiveRadius();
109  Mdouble deltaStar = (species->getUnloadingStiffnessMax()
110  / (species->getUnloadingStiffnessMax() - species->getLoadingStiffness()))
111  * species->getPenetrationDepthMax() * effectiveDiameter;
112 
113  //increase max overlap if necessary
114  if (getOverlap()>getMaxOverlap())
115  setMaxOverlap(std::min(deltaStar, getOverlap()));
116 
117  //calculate the unloading stiffness
118  Mdouble unloadingStiffness = species->getLoadingStiffness()
119  + (species->getUnloadingStiffnessMax() - species->getLoadingStiffness()) * (getMaxOverlap() / deltaStar);
120 
121  //calculate the overlap where the force is zero
122  Mdouble equilibriumOverlap = (unloadingStiffness - species->getLoadingStiffness()) / unloadingStiffness * maxOverlap_;
123 
124  //compute elastic force
125  Mdouble normalForce = unloadingStiffness * (getOverlap() - equilibriumOverlap);
126 
127  //decrease max overlap if necessary
128  Mdouble cohesiveForce = -species->getCohesionStiffness() * getOverlap();
129  if (normalForce < cohesiveForce) {
130  setMaxOverlap((unloadingStiffness + species->getCohesionStiffness())
131  / (unloadingStiffness - species->getLoadingStiffness()) * getOverlap());
132  //only necessary because the timeStep is finite:
133  normalForce = cohesiveForce;
134  }
135 
136  //add dissipative force
137  normalForce -= species->getDissipation() * getNormalRelativeVelocity();
138 
139  setAbsoluteNormalForce(std::abs(normalForce)); //used for further corce calculations;
140  setForce(getNormal() * normalForce);
141  setTorque(Vec3D(0.0, 0.0, 0.0));
142  }
143  else
144  {
146  setForce(Vec3D(0.0, 0.0, 0.0));
147  setTorque(Vec3D(0.0, 0.0, 0.0));
148  }
149 }
Mdouble getEffectiveRadius() const
Returns a Mdouble to the effective radius of the interaction. (Not corrected for the overlap) ...
Mdouble getUnloadingStiffnessMax() const
Returns the maximum unloading stiffness of the linear plastic-viscoelastic normal force...
const Vec3D & getRelativeVelocity() const
Returns a constant reference to a vector of relative velocity.
double Mdouble
void setRelativeVelocity(Vec3D relativeVelocity)
set the relative velocity of the current of the interactions.
void setForce(Vec3D force)
set total force (this is used by the normal force, tangential forces are added use addForce) ...
static Mdouble dot(const Vec3D &a, const Vec3D &b)
Calculates the dot product of two Vec3D: .
Definition: Vector.cc:167
void setNormalRelativeVelocity(Mdouble normalRelativeVelocit)
set the normal component of the relative velocity.
Mdouble getCohesionStiffness() const
Returns the cohesive stiffness of the linear plastic-viscoelastic normal force.
const Vec3D & getContactPoint() const
Gets constant reference to contact point (vector).
Mdouble getNormalRelativeVelocity() const
Returns a double which is the norm (length) of the relative velocity vector.
const Vec3D & getNormal() const
Gets the normal vector between the two interacting objects.
void setTorque(Vec3D torque)
set the total force (this is used by the normal force, tangential torques are added use addTorque) ...
Mdouble getDissipation() const
Allows the normal dissipation to be accessed.
Mdouble getOverlap() const
Returns a Mdouble with the current overlap between the two interacting objects.
void setAbsoluteNormalForce(Mdouble absoluteNormalForce)
the absolute values of the norm (length) of the normal force
BaseInteractable * getI()
const LinearPlasticViscoelasticNormalSpecies * getSpecies() const
LinearPlasticViscoelasticNormalSpecies contains the parameters used to describe a plastic-cohesive no...
BaseInteractable * getP()
Returns a pointer to first object involved in the interaction (normally a particle).
Implementation of a 3D vector (by Vitaliy).
Definition: Vector.h:45
Mdouble getPenetrationDepthMax() const
Returns the maximum penetration depth of the linear plastic-viscoelastic normal force.
Mdouble getLoadingStiffness() const
Returns the loading stiffness of the linear plastic-viscoelastic normal force.
void LinearPlasticViscoelasticInteraction::computeNormalForce ( )

Calls computeLinearPlasticViscoElasticForce().

Definition at line 153 of file LinearPlasticViscoelasticInteraction.cc.

References computeLinearPlasticViscoelasticForce().

154 {
156 }
void computeLinearPlasticViscoelasticForce()
Creates a copy of an object of this class. (Deep copy)
std::string LinearPlasticViscoelasticInteraction::getBaseName ( ) const
virtual

Returns the name of the interaction.

Returns
std::string

Definition at line 89 of file LinearPlasticViscoelasticInteraction.cc.

90 {
91  return "LinearPlasticViscoelastic";
92 }
Mdouble LinearPlasticViscoelasticInteraction::getElasticEnergy ( ) const
virtual

Computes and returns the amount of elastic energy stored in the spring.

Returns
Mdouble
Todo:
TW this is not correct; we should count the return energy

Reimplemented from BaseInteraction.

Definition at line 160 of file LinearPlasticViscoelasticInteraction.cc.

References LinearPlasticViscoelasticNormalSpecies::getLoadingStiffness(), BaseInteraction::getOverlap(), getSpecies(), and mathsFunc::square().

161 {
162  if (getOverlap() > 0)
164  else
165  return 0.0;
167 }
T square(T val)
squares a number
Definition: ExtendedMath.h:91
Mdouble getOverlap() const
Returns a Mdouble with the current overlap between the two interacting objects.
const LinearPlasticViscoelasticNormalSpecies * getSpecies() const
Mdouble getLoadingStiffness() const
Returns the loading stiffness of the linear plastic-viscoelastic normal force.
Mdouble LinearPlasticViscoelasticInteraction::getMaxOverlap ( ) const
Returns
Mdouble plasticOverlap_

Definition at line 178 of file LinearPlasticViscoelasticInteraction.cc.

References maxOverlap_.

Referenced by computeLinearPlasticViscoelasticForce(), and getUnloadingStiffness().

const LinearPlasticViscoelasticNormalSpecies * LinearPlasticViscoelasticInteraction::getSpecies ( ) const
Returns
const LinearPlasticViscoElasticNormalSpecies*

Definition at line 171 of file LinearPlasticViscoelasticInteraction.cc.

References BaseInteraction::getBaseSpecies().

Referenced by computeLinearPlasticViscoelasticForce(), getElasticEnergy(), and getUnloadingStiffness().

172 {
173  return dynamic_cast<const LinearPlasticViscoelasticNormalSpecies*>(getBaseSpecies());
174 }
const BaseSpecies * getBaseSpecies() const
Return a constant point to BaseSpecies of the interaction.
LinearPlasticViscoelasticNormalSpecies contains the parameters used to describe a plastic-cohesive no...
Mdouble LinearPlasticViscoelasticInteraction::getUnloadingStiffness ( ) const
Returns
Mdouble

Definition at line 192 of file LinearPlasticViscoelasticInteraction.cc.

References BaseInteraction::getEffectiveRadius(), LinearPlasticViscoelasticNormalSpecies::getLoadingStiffness(), getMaxOverlap(), BaseInteraction::getOverlap(), LinearPlasticViscoelasticNormalSpecies::getPenetrationDepthMax(), getSpecies(), and LinearPlasticViscoelasticNormalSpecies::getUnloadingStiffnessMax().

193 {
195  Mdouble effectiveDiameter = 2.0*getEffectiveRadius();
196  Mdouble deltaMaxFluid = species->getPenetrationDepthMax() * effectiveDiameter / (1.0-species->getLoadingStiffness()/species->getUnloadingStiffnessMax());
197  if (getOverlap() > deltaMaxFluid)
198  return species->getUnloadingStiffnessMax();
199  else
200  return species->getLoadingStiffness() + (species->getUnloadingStiffnessMax() - species->getLoadingStiffness()) * getMaxOverlap()/deltaMaxFluid;
201 }
Mdouble getEffectiveRadius() const
Returns a Mdouble to the effective radius of the interaction. (Not corrected for the overlap) ...
Mdouble getUnloadingStiffnessMax() const
Returns the maximum unloading stiffness of the linear plastic-viscoelastic normal force...
double Mdouble
Mdouble getOverlap() const
Returns a Mdouble with the current overlap between the two interacting objects.
const LinearPlasticViscoelasticNormalSpecies * getSpecies() const
LinearPlasticViscoelasticNormalSpecies contains the parameters used to describe a plastic-cohesive no...
Mdouble getPenetrationDepthMax() const
Returns the maximum penetration depth of the linear plastic-viscoelastic normal force.
Mdouble getLoadingStiffness() const
Returns the loading stiffness of the linear plastic-viscoelastic normal force.
void LinearPlasticViscoelasticInteraction::read ( std::istream &  is)
virtual

Interaction read function, which accepts an std::istream as input.

Calls the read function of BaseInteraction().

Parameters
[in,out]is

Reimplemented from BaseInteraction.

Definition at line 81 of file LinearPlasticViscoelasticInteraction.cc.

References maxOverlap_, and BaseInteraction::read().

82 {
84  helpers::readOptionalVariable<Mdouble>(is,"maxOverlap",maxOverlap_);
85 }
virtual void read(std::istream &is)
Interaction read function, which accepts an std::istream as input.
void LinearPlasticViscoelasticInteraction::setMaxOverlap ( const Mdouble  maxOverlap)
Parameters
[in]maxOverlap

Definition at line 185 of file LinearPlasticViscoelasticInteraction.cc.

References maxOverlap_.

Referenced by computeLinearPlasticViscoelasticForce().

186 {
187  maxOverlap_ = maxOverlap;
188 }
void LinearPlasticViscoelasticInteraction::write ( std::ostream &  os) const
virtual

Interaction write function, which accepts an std::ostream as input.

Calls the write function of BaseInteraction().

Parameters
[in,out]os

Reimplemented from BaseInteraction.

Definition at line 72 of file LinearPlasticViscoelasticInteraction.cc.

References maxOverlap_, and BaseInteraction::write().

73 {
75  os << " maxOverlap " << maxOverlap_;
76 }
virtual void write(std::ostream &os) const
Interaction print function, which accepts an std::ostream as input.

Member Data Documentation

Mdouble LinearPlasticViscoelasticInteraction::maxOverlap_
private

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