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LinearViscoelasticInteraction Class Reference

Enables one to compute normal forces in case of a linear visco-elastic interaction. More...

#include <LinearViscoelasticInteraction.h>

Inheritance diagram for LinearViscoelasticInteraction:

## Public Types

typedef
LinearViscoelasticNormalSpecies
SpeciesType
An alias for LinearViscoelasticNormalSpecies. More...

## Public Member Functions

LinearViscoelasticInteraction (BaseInteractable *P, BaseInteractable *I, Mdouble timeStamp)
Constructor. More...

LinearViscoelasticInteraction (const LinearViscoelasticInteraction &p)
Copy constructor. More...

virtual ~LinearViscoelasticInteraction ()
Destructor. More...

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

void read (std::istream &is)
Interaction read function, which accepts an std::istream as input. More...

void write (std::ostream &os) const
Interaction write function, which accepts an std::ostream as input. More...

std::string getBaseName () const
Returns the type/name of interaction (linear visco-elastic interaction). More...

Mdouble getElasticEnergy () const
Returns the amount of energy stored in the spring due to head on collision. More...

const
LinearViscoelasticNormalSpecies
getSpecies () const
Returns a const pointer of type LinearViscoelasticNormalSpecies*. More...

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...

virtual ~BaseInteraction ()
The default destructor. 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...

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...

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...

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...

## 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...

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 setForce (Vec3D force)
set total force (this is used by the normal force, tangential forces are added use addForce) More...

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 void reverseHistory ()
When periodic particles some interaction need certain history properties reversing. This is the function for that. More...

## Detailed Description

Enables one to compute normal forces in case of a linear visco-elastic interaction.

Definition at line 37 of file LinearViscoelasticInteraction.h.

## Member Typedef Documentation

An alias for LinearViscoelasticNormalSpecies.

Definition at line 43 of file LinearViscoelasticInteraction.h.

## Constructor & Destructor Documentation

 LinearViscoelasticInteraction::LinearViscoelasticInteraction ( BaseInteractable * P, BaseInteractable * I, Mdouble timeStamp )

Constructor.

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

Definition at line 38 of file LinearViscoelasticInteraction.cc.

39  : BaseInteraction(P, I, timeStamp)
40 {
41 #ifdef DEBUG_CONSTRUCTOR
42  std::cout<<"LinearViscoelasticInteraction::LinearViscoelasticInteraction() finished"<<std::endl;
43 #endif
44 }
BaseInteraction(BaseInteractable *P, BaseInteractable *I, Mdouble timeStamp)
A constructor takes the BaseInteractable objects which are interacting (come into contact) and time t...
 LinearViscoelasticInteraction::LinearViscoelasticInteraction ( const LinearViscoelasticInteraction & p )

Copy constructor.

Parameters
 [in] p

Definition at line 48 of file LinearViscoelasticInteraction.cc.

49  : BaseInteraction(p)
50 {
51 #ifdef DEBUG_CONSTRUCTOR
52  std::cout<<"LinearViscoelasticInteraction::LinearViscoelasticInteraction(const LinearViscoelasticInteraction& p) finished"<<std::endl;
53 #endif
54 }
BaseInteraction(BaseInteractable *P, BaseInteractable *I, Mdouble timeStamp)
A constructor takes the BaseInteractable objects which are interacting (come into contact) and time t...
 LinearViscoelasticInteraction::~LinearViscoelasticInteraction ( )
virtual

Destructor.

Definition at line 56 of file LinearViscoelasticInteraction.cc.

57 {
58 #ifdef DEBUG_DESTRUCTOR
59  std::cout<<"LinearViscoelasticInteraction::~LinearViscoelasticInteraction() finished"<<std::endl;
60 #endif
61 }

## Member Function Documentation

 void LinearViscoelasticInteraction::computeNormalForce ( )

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

Computes the normal force caused due to normal collision between particles or particle-wall.

Definition at line 89 of file LinearViscoelasticInteraction.cc.

90 {
91  // Compute the relative velocity vector of particle P w.r.t. I
92  setRelativeVelocity(getP()->getVelocityAtContact(getContactPoint()) - getI()->getVelocityAtContact(getContactPoint()));
93  // Compute the projection of vrel onto the normal (can be negative)
95
96  if (getOverlap() > 0) //if contact forces
97  {
99
100  Mdouble normalForce = species->getStiffness() * getOverlap() - species->getDissipation() * getNormalRelativeVelocity();
101  setAbsoluteNormalForce(std::abs(normalForce)); //used for further corce calculations;
102  setForce(getNormal() * normalForce);
103  setTorque(Vec3D(0.0, 0.0, 0.0));
104  }
105  else
106  {
108  setForce(Vec3D(0.0, 0.0, 0.0));
109  setTorque(Vec3D(0.0, 0.0, 0.0));
110  }
111 }
Mdouble getStiffness() const
Allows the spring constant to be accessed.
Mdouble getDissipation() const
Allows the normal dissipation to be accessed.
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:187
void setNormalRelativeVelocity(Mdouble normalRelativeVelocit)
set the normal component of the relative velocity.
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.
LinearViscoelasticNormalSpecies contains the parameters used to describe a linear elastic-dissipative...
const LinearViscoelasticNormalSpecies * getSpecies() const
Returns a const pointer of type LinearViscoelasticNormalSpecies*.
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 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()
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
 std::string LinearViscoelasticInteraction::getBaseName ( ) const

Returns the type/name of interaction (linear visco-elastic interaction).

Returns
std::string

Definition at line 82 of file LinearViscoelasticInteraction.cc.

83 {
84  return "LinearViscoelastic";
85 }
 Mdouble LinearViscoelasticInteraction::getElasticEnergy ( ) const
virtual

Returns the amount of energy stored in the spring due to head on collision.

Returns
Mdouble

Reimplemented from BaseInteraction.

Definition at line 115 of file LinearViscoelasticInteraction.cc.

116 {
117  if (getOverlap() > 0)
118  return 0.5 * (getSpecies()->getStiffness() * mathsFunc::square(getOverlap()));
119  else
120  return 0.0;
121 }
Mdouble getStiffness() const
Allows the spring constant to be accessed.
T square(T val)
squares a number
Definition: ExtendedMath.h:91
const LinearViscoelasticNormalSpecies * getSpecies() const
Returns a const pointer of type LinearViscoelasticNormalSpecies*.
Mdouble getOverlap() const
Returns a Mdouble with the current overlap between the two interacting objects.
 const LinearViscoelasticNormalSpecies * LinearViscoelasticInteraction::getSpecies ( ) const

Returns a const pointer of type LinearViscoelasticNormalSpecies*.

Returns
const LinearViscoelasticNormalSpecies*

Definition at line 125 of file LinearViscoelasticInteraction.cc.

References BaseInteraction::getBaseSpecies().

Referenced by computeNormalForce(), and getElasticEnergy().

126 {
127  return dynamic_cast<const LinearViscoelasticNormalSpecies*>(getBaseSpecies());
128 }
LinearViscoelasticNormalSpecies contains the parameters used to describe a linear elastic-dissipative...
const BaseSpecies * getBaseSpecies() const
Return a constant point to BaseSpecies of the interaction.
 void LinearViscoelasticInteraction::read ( std::istream & is )
virtual

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

Calls the BaseInteraction() read function.

Parameters
 [in,out] is

Reimplemented from BaseInteraction.

Definition at line 75 of file LinearViscoelasticInteraction.cc.

76 {
78 }
virtual void read(std::istream &is)
Interaction read function, which accepts an std::istream as input.
 void LinearViscoelasticInteraction::write ( std::ostream & os ) const
virtual

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

Calls the BaseInteraction() write function.

Parameters
 [in,out] os

Reimplemented from BaseInteraction.

Definition at line 67 of file LinearViscoelasticInteraction.cc.

References BaseInteraction::write().

68 {
70 }
virtual void write(std::ostream &os) const
Interaction print function, which accepts an std::ostream as input.

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