MercuryDPM  Trunk
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Macros Pages
HertzianViscoelasticInteraction.cc
Go to the documentation of this file.
1 //Copyright (c) 2013-2020, The MercuryDPM Developers Team. All rights reserved.
2 //For the list of developers, see <http://www.MercuryDPM.org/Team>.
3 //
4 //Redistribution and use in source and binary forms, with or without
5 //modification, are permitted provided that the following conditions are met:
6 // * Redistributions of source code must retain the above copyright
7 // notice, this list of conditions and the following disclaimer.
8 // * Redistributions in binary form must reproduce the above copyright
9 // notice, this list of conditions and the following disclaimer in the
10 // documentation and/or other materials provided with the distribution.
11 // * Neither the name MercuryDPM nor the
12 // names of its contributors may be used to endorse or promote products
13 // derived from this software without specific prior written permission.
14 //
15 //THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
16 //ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17 //WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 //DISCLAIMED. IN NO EVENT SHALL THE MERCURYDPM DEVELOPERS TEAM BE LIABLE FOR ANY
19 //DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
20 //(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21 //LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
22 //ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 //(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
24 //SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 
26 
29 #include "Species/BaseSpecies.h"
30 #include "BaseInteractable.h"
31 #include "InteractionHandler.h"
32 #include <iomanip>
33 #include <fstream>
34 
41  unsigned timeStamp)
42  : BaseInteraction(P, I, timeStamp)
43 {
44 #ifdef DEBUG_CONSTRUCTOR
45  std::cout<<"HertzianViscoelasticInteraction::HertzianViscoelasticInteraction() finished"<<std::endl;
46 #endif
47 }
48 
53  : BaseInteraction(p)
54 {
55 #ifdef DEBUG_CONSTRUCTOR
56  std::cout<<"HertzianViscoelasticInteraction::HertzianViscoelasticInteraction(const HertzianViscoelasticInteraction& p) finished"<<std::endl;
57 #endif
58 }
59 
61 
66 {
67 #ifdef DEBUG_DESTRUCTOR
68  std::cout<<"HertzianViscoelasticInteraction::~HertzianViscoelasticInteraction() finished"<<std::endl;
69 #endif
70 }
71 
75 void HertzianViscoelasticInteraction::write(std::ostream& os) const
76 {
78 }
79 
84 {
86 }
87 
92 {
93  return "HertzianViscoelastic";
94 }
95 
107 {
108  // This function is called for all particles within interactionRadius distance.
109 
110  // This has to be outside the loop because it is needed for the other forces
111  // Compute the relative velocity vector of particle P w.r.t. I
113  getP()->getVelocityAtContact(getContactPoint()) - getI()->getVelocityAtContact(getContactPoint()));
114  // Compute the projection of vrel onto the normal (can be negative)
116 
117  if (getOverlap() > 0) //if contact forces
118  {
120 
121  Mdouble stiffness = 4. / 3. * species->getEffectiveElasticModulus() * std::sqrt(getEffectiveRadius() * getOverlap());
122 
123  //calculating the current normal force
124  //dissipation is computed such that the restitution is constant
125  Mdouble dissipationCoefficient = species->getDissipation() * sqrt(getEffectiveMass() * stiffness);
126  Mdouble normalForce = stiffness * getOverlap() - dissipationCoefficient * getNormalRelativeVelocity();
127 
128  //setting the normal force parameter in the base interaction class so that it can be accessed
129  //by other classes...
130  setAbsoluteNormalForce(std::abs(normalForce)); //used for further force calculations;
131  setForce(getNormal() * normalForce);
133  setTorque(Vec3D(0.0, 0.0, 0.0));
134  }
135  else
136  {
138  setForce(Vec3D(0.0, 0.0, 0.0));
139  setTorque(Vec3D(0.0, 0.0, 0.0));
140  }
141 }
142 
149 {
150  if (getOverlap() > 0)
151  {
152  return 8. / 15. * getSpecies()->getEffectiveElasticModulus() * std::sqrt(getEffectiveRadius() * getOverlap()) *
154  }
155  else
156  {
157  return 0.0;
158  }
159 }
160 
165 {
166  return static_cast<const HertzianViscoelasticNormalSpecies*>(getBaseSpecies()->getNormalForce());
167 }
168 
177 {
179  const Mdouble modulus = 4. / 3. * species->getEffectiveElasticModulus() * std::sqrt(getEffectiveRadius());
180  const Mdouble equilibriumOverlap = std::cbrt(mathsFunc::square(adhesiveForce / modulus));
181  return 0.6 * adhesiveForce * equilibriumOverlap;//why not 0.4?
182 }
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 getElasticEnergyAtEquilibrium(Mdouble adhesiveForce) const override
double Mdouble
Definition: GeneralDefine.h:34
std::string getBaseName() const
Returns the name of the interaction.
const Vec3D & getRelativeVelocity() const
Returns a constant reference to a vector of relative velocity.
Mdouble getElasticEnergy() const override
Computes and returns the amount of elastic energy stored in the spring.
Computes normal forces for a Herztian visco-elastic interaction.
void setRelativeVelocity(Vec3D relativeVelocity)
set the relative velocity of the current of the interactions.
BaseNormalForce * getNormalForce() const
Definition: BaseSpecies.h:148
void setForce(Vec3D force)
set total force (this is used by the normal force, tangential forces are added use addForce) ...
const Vec3D & getContactPoint() const
Gets constant reference to contact point (vector).
BaseInteractable * getI()
Returns a pointer to the second object involved in the interaction (often a wall or a particle)...
static Mdouble dot(const Vec3D &a, const Vec3D &b)
Calculates the dot product of two Vec3D: .
Definition: Vector.cc:76
void setNormalRelativeVelocity(Mdouble normalRelativeVelocit)
set the normal component of the relative velocity.
Stores information about interactions between two interactable objects; often particles but could be ...
const Vec3D & getNormal() const
Gets the normal vector between the two interacting objects.
BaseInteractable * getP()
Returns a pointer to first object involved in the interaction (normally a particle).
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.
void write(std::ostream &os) const override
Interaction write function, which accepts an std::ostream as input.
Mdouble getDissipation() const
Allows the normal dissipation to be accessed.
void computeNormalForce()
Computes the amount of normal force due to an Hertzian 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.
Mdouble getEffectiveElasticModulus() const
Allows the spring constant to be accessed.
void setAbsoluteNormalForce(Mdouble absoluteNormalForce)
the absolute values of the norm (length) of the normal force
void read(std::istream &is) override
Interaction read function, which accepts an std::istream as input.
void read(std::istream &is) override
Interaction read function, which accepts an std::istream as input.
Defines the basic properties that a interactable object can have.
Definition: Vector.h:49
T square(const T val)
squares a number
Definition: ExtendedMath.h:104
void write(std::ostream &os) const override
Interaction print function, which accepts an std::ostream as input.
HertzianViscoelasticNormalSpecies contains the parameters used to describe a Hertzian normal force (T...
Mdouble getEffectiveMass() const
Returns a Mdouble to the effective radius of the interaction. (Not corrected for the overlap) ...