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HertzianViscoelasticInteraction.cc
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25 
26 
29 #include "BaseInteractable.h"
30 #include "InteractionHandler.h"
31 #include <iomanip>
32 #include <fstream>
39  : BaseInteraction(P, I, timeStamp)
40 {
41 #ifdef DEBUG_CONSTRUCTOR
42  std::cout<<"HertzianViscoelasticInteraction::HertzianViscoelasticInteraction() finished"<<std::endl;
43 #endif
44 }
49  : BaseInteraction(p)
50 {
51 #ifdef DEBUG_CONSTRUCTOR
52  std::cout<<"HertzianViscoelasticInteraction::HertzianViscoelasticInteraction(const HertzianViscoelasticInteraction& p) finished"<<std::endl;
53 #endif
54 }
59 {
60 #ifdef DEBUG_DESTRUCTOR
61  std::cout<<"HertzianViscoelasticInteraction::~HertzianViscoelasticInteraction() finished"<<std::endl;
62 #endif
63 }
64 
68 void HertzianViscoelasticInteraction::write(std::ostream& os) const
69  {
71 }
76 {
78 }
83 {
84  return "HertzianViscoelastic";
85 }
90 {
92  // Compute the relative velocity vector of particle P w.r.t. I
93  setRelativeVelocity(getP()->getVelocityAtContact(getContactPoint()) - getI()->getVelocityAtContact(getContactPoint()));
94  // Compute the projection of vrel onto the normal (can be negative)
96 
97  if (getOverlap() > 0) //if contact forces
98  {
100 
101  Mdouble stiffness = 4. / 3. * species->getElasticModulus() * std::sqrt(getEffectiveRadius() * getOverlap());
102 
103  //calculating the current normal force
104  //dissipation is computed such that the restitution is constant
105  Mdouble normalForce = stiffness * getOverlap() - species->getDissipation() * getNormalRelativeVelocity();
106 
107  //setting the normal force parameter in the base interaction class so that it can be accessed
108  //by other classes...
109  setAbsoluteNormalForce(std::abs(normalForce)); //used for further force calculations;
110  setForce(getNormal() * normalForce);
112  setTorque(Vec3D(0.0, 0.0, 0.0));
113  }
114  else
115  {
117  setForce(Vec3D(0.0, 0.0, 0.0));
118  setTorque(Vec3D(0.0, 0.0, 0.0));
119  }
120 }
125 {
126  if (getOverlap() > 0)
127  return 0.5 * (getSpecies()->getElasticModulus() * mathsFunc::square(getOverlap()));
128  else
129  return 0.0;
131 }
136 {
137  return dynamic_cast<const HertzianViscoelasticNormalSpecies*>(getBaseSpecies());
138 }
Mdouble getEffectiveRadius() const
Returns a Mdouble to the effective radius of the interaction. (Not corrected for the overlap) ...
const HertzianViscoelasticNormalSpecies * getSpecies() const
Returns a const pointer of type HerztianViscoelasticNormalSpecies (dynamic-cast). ...
Mdouble getElasticModulus() const
Allows the spring constant to be accessed.
std::string getBaseName() const
Returns the name of the interaction.
const Vec3D & getRelativeVelocity() const
Returns a constant reference to a vector of relative velocity.
Computes normal forces for a Herztian visco-elastic interaction.
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.
T square(T val)
squares a number
Definition: ExtendedMath.h:91
Stores information about interactions between two interactable objects; often particles but could be ...
HertzianViscoelasticInteraction(BaseInteractable *P, BaseInteractable *I, Mdouble timeStamp)
Constructor.
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 BaseSpecies * getBaseSpecies() const
Return a constant point to BaseSpecies of the interaction.
Mdouble getDissipation() const
Allows the normal dissipation to be accessed.
const Vec3D & getNormal() const
Gets the normal vector between the two interacting objects.
void computeNormalForce()
Computes the amount of normal force due to an Herztian visco-elastic interaction. ...
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()
void read(std::istream &is)
Interaction read function, which accepts an std::istream as input.
void write(std::ostream &os) const
Interaction write function, which accepts an std::ostream as input.
virtual void read(std::istream &is)
Interaction read function, which accepts an std::istream as input.
Defines the basic properties that a interactable object can have.
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
HertzianViscoelasticNormalSpecies contains the parameters used to describe a Hertzian normal force (T...
virtual void write(std::ostream &os) const
Interaction print function, which accepts an std::ostream as input.
Mdouble getElasticEnergy() const
Computes and returns the amount of elastic energy stored in the spring.