SinterNormalSpecies Class Reference

SinterNormalSpecies contains the parameters used to describe a plastic-cohesive normal force (Stefan Ludings plastic-cohesive force model). More...

#include <SinterNormalSpecies.h>

Inheritance diagram for SinterNormalSpecies:

Public Types
typedef SinterInteraction	InteractionType
	The correct Interaction type for this FrictionForceSpecies. More...

Public Member Functions
	SinterNormalSpecies ()
	The default constructor. More...
	SinterNormalSpecies (const SinterNormalSpecies &p)
	The default copy constructor. More...
	~SinterNormalSpecies ()
	The default destructor. More...
void	read (std::istream &is)
	Reads the species properties from an input stream. More...
void	write (std::ostream &os) const
	Writes the species properties to an output stream. More...
std::string	getBaseName () const
	Used in Species::getName to obtain a unique name for each Species. More...
void	mix (SinterNormalSpecies *S, SinterNormalSpecies *T)
	creates default values for mixed species More...
void	setCollisionTimeAndRestitutionCoefficient (Mdouble tc, Mdouble eps, Mdouble mass)
void	setStiffnessAndRestitutionCoefficient (Mdouble k_, Mdouble eps, Mdouble mass)
	Sets k, disp such that it matches a given tc and eps for a collision of two copies of P. More...
Mdouble	getCollisionTime (Mdouble mass)
	Calculates collision time for two copies of a particle of given disp, k, mass. More...
void	setPlasticParameters (Mdouble loadingStiffness, Mdouble unloadingStiffnessMax, Mdouble cohesionStiffness, Mdouble penetrationDepthMax)
	Sets all parameters of the linear plastic-viscoelastic normal force at once. More...
Mdouble	getLoadingStiffness () const
	Returns the loading stiffness of the linear plastic-viscoelastic normal force. More...
Mdouble	getUnloadingStiffnessMax () const
	Returns the maximum unloading stiffness of the linear plastic-viscoelastic normal force. More...
Mdouble	getCohesionStiffness () const
	Returns the cohesive stiffness of the linear plastic-viscoelastic normal force. More...
Mdouble	getPenetrationDepthMax () const
	Returns the maximum penetration depth of the linear plastic-viscoelastic normal force. More...
void	setLoadingStiffness (Mdouble loadingStiffness)
	Sets the loading stiffness of the linear plastic-viscoelastic normal force. More...
void	setUnloadingStiffnessMax (Mdouble unloadingStiffnessMax)
	Sets the maximum unloading stiffness of the linear plastic-viscoelastic normal force. More...
void	setCohesionStiffness (Mdouble cohesionStiffness)
	Sets the cohesive stiffness of the linear plastic-viscoelastic normal force. More...
void	setPenetrationDepthMax (Mdouble penetrationDepthMax)
	Sets the maximum penetration depth of the linear plastic-viscoelastic normal force. More...
void	setDissipation (Mdouble dissipation)
	Sets the linear dissipation coefficient of the linear plastic-viscoelastic normal force. More...
Mdouble	getDissipation () const
	Allows the normal dissipation to be accessed. More...
void	setSinterAdhesion (Mdouble sinterAdhesion)
	Sets sinterAdhesion_. More...
Mdouble	getSinterAdhesion () const
	Accesses sinterAdhesion_. More...
void	setInverseSinterViscosity (Mdouble inverseSinterViscosity)
	Sets inverseSinterViscosity_. More...
Mdouble	getInverseSinterViscosity () const
	Accesses inverseSinterViscosity_. More...
MERCURYDPM_DEPRECATED void	setLoadingStiffnessAndDissipation (helpers::KAndDisp new_)
	Allows the spring and dissipation constants to be changed simultaneously. More...
Mdouble	computeTimeStep (Mdouble mass)
	Returns the optimal time step to resolve a collision of two particles of a given mass. More...
void	setSinterForceAndTime (Mdouble adhesionForce, Mdouble sinterTime, Mdouble radius)
void	setParhamiMcKeeping (Mdouble alpha, Mdouble beta, Mdouble atomicVolume, Mdouble surfaceEnergy, Mdouble thicknessDiffusion, Mdouble activationEnergy, Mdouble temperature)
	Sets the sinterAdhesion_ and inverseSinterViscosity_ based on the Parhami-McKeeping parameters. More...
void	setSinterRate (Mdouble sinterRate)
	Sets sinterRate_. More...
void	setSinterType (SINTERTYPE sinterType)
	Sets sinterRate_. More...
Mdouble	getSinterRate () const
	Accesses sinterRate_. More...
SINTERTYPE	getSinterType () const
std::function< double(double temperature)>	getTemperatureDependentSinterRate () const
double	getTemperatureDependentSinterRate (double temperature) const
void	setTemperatureDependentSinterRate (std::function< double(double temperature)> temperatureDependentSinterRate)
void	setComplianceZero (Mdouble complianceZero)
Mdouble	getComplianceZero () const
void	setSurfTension (Mdouble complianceZero)
Mdouble	getSurfTension () const
void	setConstantC1 (Mdouble constantC1_)
Mdouble	getConstantC1 () const
void	setSeparationDis (Mdouble separationDis)
Mdouble	getSeparationDis () const
Public Member Functions inherited from BaseNormalForce
	BaseNormalForce ()
	BaseNormalForce (const BaseNormalForce &p)
bool	getConstantRestitution () const
void	setConstantRestitution (bool constantRestitution)
virtual void	actionsAfterTimeStep (BaseParticle *particle) const
Public Member Functions inherited from BaseForce
BaseSpecies *	getBaseSpecies () const
void	setBaseSpecies (BaseSpecies *baseSpecies)

Private Attributes
Mdouble	loadingStiffness_
	(normal) spring constant (k_1) More...
Mdouble	unloadingStiffnessMax_
	the maximum elastic constant (k_2^max) for plastic deformations More...
Mdouble	cohesionStiffness_
	the adhesive spring constant (k^c) for plastic deformations More...
Mdouble	penetrationDepthMax_
	the depth (relative to the normalized radius) at which k_2^max is used (phi_f) More...
Mdouble	dissipation_
	linear dissipation coefficient More...
Mdouble	sinterAdhesion_
Mdouble	inverseSinterViscosity_
Mdouble	sinterRate_
Mdouble	complianceZero_
Mdouble	surfTension_
Mdouble	constantC1_
Mdouble	separationDis_
SINTERTYPE	sinterType_
	sinterType options determin how the rate of sintering, d(equilibriumOverlap)/dt is computed PARHAMI_MCKEEPING: sinter rate given by (sinterAdhesion+normalForce)/sinterViscosity CONSTANT_RATE: sinter rate given by sinterRate More...
std::function< double(double temperature)>	temperatureDependentSinterRate_

Detailed Description

SinterNormalSpecies contains the parameters used to describe a plastic-cohesive normal force (Stefan Ludings plastic-cohesive force model).

See SinterNormalInteraction::computeForce for a description of the force law.

Member Typedef Documentation

InteractionType

typedef SinterInteraction SinterNormalSpecies::InteractionType

The correct Interaction type for this FrictionForceSpecies.

Constructor & Destructor Documentation

SinterNormalSpecies() [1/2]

SinterNormalSpecies::SinterNormalSpecies

(

)

The default constructor.

        : BaseNormalForce()
{
    sinterType_ = SINTERTYPE::PARHAMI_MCKEEPING;
    loadingStiffness_ = 0.0;
    unloadingStiffnessMax_ = 0.0;
    cohesionStiffness_ = 0.0;
    penetrationDepthMax_ = 0.0;
    dissipation_ = 0.0;
    sinterAdhesion_ = 0.0;
    sinterRate_ = 0.0;
    inverseSinterViscosity_ = 0.0;
    complianceZero_ = 0.0;
    surfTension_ = 0.0;
    constantC1_ = 0.0;
    separationDis_ = 0.0;
#ifdef DEBUG_CONSTRUCTOR
    std::cout<<"SinterNormalSpecies::SinterNormalSpecies() finished"<<std::endl;
#endif
}

References cohesionStiffness_, complianceZero_, constantC1_, dissipation_, inverseSinterViscosity_, loadingStiffness_, PARHAMI_MCKEEPING, penetrationDepthMax_, separationDis_, sinterAdhesion_, sinterRate_, sinterType_, surfTension_, and unloadingStiffnessMax_.

SinterNormalSpecies() [2/2]

SinterNormalSpecies::SinterNormalSpecies

(

const SinterNormalSpecies &

p

)

The default copy constructor.

Parameters

[in]

the

species that is copied

        : BaseNormalForce(p)
{
    sinterType_ = p.sinterType_;
    loadingStiffness_ = p.loadingStiffness_;
    unloadingStiffnessMax_ = p.unloadingStiffnessMax_;
    cohesionStiffness_ = p.cohesionStiffness_;
    penetrationDepthMax_ = p.penetrationDepthMax_;
    dissipation_ = p.dissipation_;
    sinterAdhesion_ = p.sinterAdhesion_;
    inverseSinterViscosity_ = p.inverseSinterViscosity_;
    sinterRate_ = p.sinterRate_;
    complianceZero_ = p.complianceZero_;
    surfTension_ = p.surfTension_;
    constantC1_ = p.constantC1_;
    separationDis_ = p.separationDis_;
#ifdef DEBUG_CONSTRUCTOR
    std::cout<<"SinterNormalSpecies::SinterNormalSpecies(const SinterNormalSpecies &p) finished"<<std::endl;
#endif
}

References cohesionStiffness_, complianceZero_, constantC1_, dissipation_, inverseSinterViscosity_, loadingStiffness_, penetrationDepthMax_, separationDis_, sinterAdhesion_, sinterRate_, sinterType_, surfTension_, and unloadingStiffnessMax_.

~SinterNormalSpecies()

SinterNormalSpecies::~SinterNormalSpecies

(

)

The default destructor.

{
#ifdef DEBUG_DESTRUCTOR
    std::cout<<"SinterNormalSpecies::~SinterNormalSpecies() finished"<<std::endl;
#endif
}

Member Function Documentation

computeTimeStep()

Mdouble SinterNormalSpecies::computeTimeStep

(

Mdouble

mass

)

Returns the optimal time step to resolve a collision of two particles of a given mass.

Calculates collision time for stiffest spring constant, divides by 50

Parameters

[in]

mass

the optimal time step is computed to resolve a collision of two particles of this mass.

{
    if (unloadingStiffnessMax_ / (.5 * mass) < mathsFunc::square(dissipation_ / mass))
    {
        logger(ERROR, "Dissipation too high; max. allowed %", sqrt(2.0 * unloadingStiffnessMax_ * mass));
    }
    return 0.02 * constants::pi /
           std::sqrt(unloadingStiffnessMax_ / (.5 * mass) - mathsFunc::square(dissipation_ / mass));
}

References dissipation_, ERROR, logger, constants::pi, mathsFunc::square(), and unloadingStiffnessMax_.

getBaseName()

std::string SinterNormalSpecies::getBaseName

(

)

const

Used in Species::getName to obtain a unique name for each Species.

Returns

a string containing the name of the species (minus the word "Species")

{
    return "Sinter";
}

getCohesionStiffness()

Mdouble SinterNormalSpecies::getCohesionStiffness

(

)

const

Returns the cohesive stiffness of the linear plastic-viscoelastic normal force.

Returns

the cohesive stiffness of the linear plastic-viscoelastic normal force.

{
    return cohesionStiffness_;
}

References cohesionStiffness_.

Referenced by SinterInteraction::computeNormalForce(), and mix().

getCollisionTime()

Mdouble SinterNormalSpecies::getCollisionTime

(

Mdouble

mass

)

Calculates collision time for two copies of a particle of given disp, k, mass.

{
    if (mass <= 0)
    {
        logger(ERROR, "Error in getCollisionTime(%) mass is not set or has an unexpected value, (getCollisionTime(%))",
               mass, mass);
    }
    if (loadingStiffness_ <= 0)
    {
        logger(ERROR, "Error in getCollisionTime(%) stiffness=% is not set or has an unexpected value "
                      "(getCollisionTime(%), with stiffness=%)",
               mass, loadingStiffness_, mass, loadingStiffness_);
    }
    if (dissipation_ < 0)
    {
        logger(ERROR, "Error in getCollisionTime(%) dissipation=%"
                      " is not set or has an unexpected value, (getCollisionTime(%), with dissipation=%)",
               mass, dissipation_, mass, dissipation_);
    }
    Mdouble tosqrt = loadingStiffness_ / (.5 * mass) - mathsFunc::square(dissipation_ / mass);
    if (tosqrt <= -1e-8 * loadingStiffness_ / (.5 * mass))
    {
        logger(ERROR, "Error in getCollisionTime(%) values for mass, stiffness and dissipation would lead to an "
                      "overdamped system, (getCollisionTime(%), with stiffness=% and dissipation=%)",
               mass, mass, loadingStiffness_, dissipation_);
    }
    return constants::pi / std::sqrt(tosqrt);
}

References dissipation_, ERROR, loadingStiffness_, logger, constants::pi, and mathsFunc::square().

getComplianceZero()

Mdouble SinterNormalSpecies::getComplianceZero

(

)

const

{
    return complianceZero_;
}

References complianceZero_.

Referenced by SinterInteraction::computeNormalForce(), and mix().

getConstantC1()

Mdouble SinterNormalSpecies::getConstantC1

(

)

const

{
    return constantC1_;
}

References constantC1_.

Referenced by SinterInteraction::computeNormalForce(), and mix().

getDissipation()

Mdouble SinterNormalSpecies::getDissipation

(

)

const

Allows the normal dissipation to be accessed.

Returns

the linear dissipation coefficient

{
    return dissipation_;
}

References dissipation_.

Referenced by SinterInteraction::computeNormalForce(), and mix().

getInverseSinterViscosity()

Mdouble SinterNormalSpecies::getInverseSinterViscosity

(

)

const

Accesses inverseSinterViscosity_.

Returns

value of inverseSinterViscosity_

{
    return inverseSinterViscosity_;
}

References inverseSinterViscosity_.

Referenced by mix(), setParhamiMcKeeping(), and setSinterForceAndTime().

getLoadingStiffness()

Mdouble SinterNormalSpecies::getLoadingStiffness

(

)

const

Returns the loading stiffness of the linear plastic-viscoelastic normal force.

Returns

the loading stiffness of the linear plastic-viscoelastic normal force.

{
    return loadingStiffness_;
}

References loadingStiffness_.

Referenced by SinterInteraction::computeNormalForce(), SinterInteraction::getElasticEnergy(), SinterInteraction::getUnloadingStiffness(), and mix().

getPenetrationDepthMax()

Mdouble SinterNormalSpecies::getPenetrationDepthMax

(

)

const

Returns the maximum penetration depth of the linear plastic-viscoelastic normal force.

Returns

the maximum penetration depth of the linear plastic-viscoelastic normal force.

{
    return penetrationDepthMax_;
}

References penetrationDepthMax_.

Referenced by SinterInteraction::computeNormalForce(), SinterInteraction::getUnloadingStiffness(), and mix().

getSeparationDis()

Mdouble SinterNormalSpecies::getSeparationDis

(

)

const

{
    return separationDis_;
}

References separationDis_.

Referenced by SinterInteraction::computeNormalForce(), and mix().

getSinterAdhesion()

Mdouble SinterNormalSpecies::getSinterAdhesion

(

)

const

Accesses sinterAdhesion_.

Returns

value of sinterAdhesion_

{
    return sinterAdhesion_;
}

References sinterAdhesion_.

Referenced by SinterInteraction::computeNormalForce(), mix(), setParhamiMcKeeping(), and setSinterForceAndTime().

getSinterRate()

Mdouble SinterNormalSpecies::getSinterRate

(

)

const

Accesses sinterRate_.

Returns

value of sinterAdhesion_

{
    return sinterRate_;
}

References sinterRate_.

Referenced by SinterInteraction::computeNormalForce().

getSinterType()

SINTERTYPE SinterNormalSpecies::getSinterType

(

)

const

{
    return sinterType_;
}

References sinterType_.

Referenced by SinterInteraction::computeNormalForce().

getSurfTension()

Mdouble SinterNormalSpecies::getSurfTension

(

)

const

{
    return surfTension_;
}

References surfTension_.

Referenced by SinterInteraction::computeNormalForce(), and mix().

getTemperatureDependentSinterRate() [1/2]

std::function< double(double temperature)> SinterNormalSpecies::getTemperatureDependentSinterRate

(

)

const

{
    return temperatureDependentSinterRate_;
}

References temperatureDependentSinterRate_.

Referenced by SinterInteraction::computeNormalForce().

getTemperatureDependentSinterRate() [2/2]

double SinterNormalSpecies::getTemperatureDependentSinterRate

(

double

temperature

)

const

{
    return temperatureDependentSinterRate_(temperature);
}

References temperatureDependentSinterRate_.

getUnloadingStiffnessMax()

Mdouble SinterNormalSpecies::getUnloadingStiffnessMax

(

)

const

Returns the maximum unloading stiffness of the linear plastic-viscoelastic normal force.

Returns

the maximum unloading stiffness of the linear plastic-viscoelastic normal force.

{
    return unloadingStiffnessMax_;
}

References unloadingStiffnessMax_.

Referenced by SinterInteraction::computeNormalForce(), SinterInteraction::getUnloadingStiffness(), and mix().

mix()

void SinterNormalSpecies::mix	(	SinterNormalSpecies *	S,
		SinterNormalSpecies *	T
	)

creates default values for mixed species

For all parameters we assume that the harmonic mean of the parameters of the original two species is a sensible default.

Parameters

[in]

S,T

the two species whose properties are mixed to create the new species

{
    loadingStiffness_ = BaseSpecies::average(S->getLoadingStiffness(), T->getLoadingStiffness());
    unloadingStiffnessMax_ = BaseSpecies::average(S->getUnloadingStiffnessMax(), T->getUnloadingStiffnessMax());
    cohesionStiffness_ = BaseSpecies::average(S->getCohesionStiffness(), T->getCohesionStiffness());
    penetrationDepthMax_ = BaseSpecies::average(S->getPenetrationDepthMax(), T->getPenetrationDepthMax());
    dissipation_ = BaseSpecies::average(S->getDissipation(), T->getDissipation());
    inverseSinterViscosity_ = BaseSpecies::average(S->getInverseSinterViscosity(), T->getInverseSinterViscosity());
    sinterAdhesion_ = BaseSpecies::average(S->getSinterAdhesion(), T->getSinterAdhesion());
    complianceZero_ = BaseSpecies::average(S->getComplianceZero(), T->getComplianceZero());
    surfTension_ = BaseSpecies::average(S->getSurfTension(), T->getSurfTension());
    constantC1_= BaseSpecies::average(S->getConstantC1(), T->getConstantC1());
    separationDis_ = BaseSpecies::average(S->getSeparationDis(), T->getSeparationDis());
 
}

References BaseSpecies::average(), cohesionStiffness_, complianceZero_, constantC1_, dissipation_, getCohesionStiffness(), getComplianceZero(), getConstantC1(), getDissipation(), getInverseSinterViscosity(), getLoadingStiffness(), getPenetrationDepthMax(), getSeparationDis(), getSinterAdhesion(), getSurfTension(), getUnloadingStiffnessMax(), inverseSinterViscosity_, loadingStiffness_, penetrationDepthMax_, separationDis_, sinterAdhesion_, surfTension_, and unloadingStiffnessMax_.

read()

void SinterNormalSpecies::read

(

std::istream &

is

)

Reads the species properties from an input stream.

Parameters

[in]

is

input stream (typically the restart file)

{
    std::string dummy;
    is >> dummy >> loadingStiffness_;
    is >> dummy >> unloadingStiffnessMax_;
    is >> dummy >> cohesionStiffness_;
    is >> dummy >> penetrationDepthMax_;
    is >> dummy >> dissipation_;
    is >> dummy >> sinterAdhesion_;
    is >> dummy >> inverseSinterViscosity_;
    is >> dummy >> sinterRate_;
    is >> dummy >> complianceZero_;
    is >> dummy >> surfTension_;
    is >> dummy >> constantC1_;
    is >> dummy >> separationDis_;
    unsigned type;
    is >> dummy >> type;
    sinterType_ = (SINTERTYPE) type;
}

References cohesionStiffness_, complianceZero_, constantC1_, dissipation_, inverseSinterViscosity_, loadingStiffness_, penetrationDepthMax_, separationDis_, sinterAdhesion_, sinterRate_, sinterType_, surfTension_, and unloadingStiffnessMax_.

setCohesionStiffness()

void SinterNormalSpecies::setCohesionStiffness

(

Mdouble

cohesionStiffness

)

Sets the cohesive stiffness of the linear plastic-viscoelastic normal force.

Parameters

[in]

cohesionStiffness

the cohesive stiffness of the linear plastic-viscoelastic normal force.

{
    cohesionStiffness_ = cohesionStiffness;
}

References cohesionStiffness_.

Referenced by setPlasticParameters().

setCollisionTimeAndRestitutionCoefficient()

void SinterNormalSpecies::setCollisionTimeAndRestitutionCoefficient	(	Mdouble	tc,
		Mdouble	eps,
		Mdouble	mass
	)

Set k, disp such that is matches a given tc and eps for a collision of two different masses. Recall the resitution constant is a function of k, disp and the mass of each particle in the collision See also setCollisionTimeAndRestitutionCoefficient(Mdouble tc, Mdouble eps, Mdouble mass)

Sets k, disp such that it matches a given tc and eps for a collision of two copies of equal mass m

Parameters

[in]	tc	collision time
[in]	eps	restitution coefficient
[in]	mass	effective particle mass, \(\frac{2}{1/m1+1/m2}\)

Todo:

TW: check that the masses are described correctly here (m_eff or m_p?))

{
    if (eps == 0.0)
    {
        loadingStiffness_ = .5 * mass * mathsFunc::square(constants::pi / tc);
        dissipation_ = std::sqrt(2.0 * mass * loadingStiffness_);
    }
    else
    {
        dissipation_ = -mass / tc * std::log(eps);
        loadingStiffness_ =
                .5 * mass * (mathsFunc::square(constants::pi / tc) + mathsFunc::square(dissipation_ / mass));
    }
    unloadingStiffnessMax_ = loadingStiffness_;
}

References dissipation_, loadingStiffness_, mathsFunc::log(), constants::pi, mathsFunc::square(), and unloadingStiffnessMax_.

setComplianceZero()

void SinterNormalSpecies::setComplianceZero

(

Mdouble

complianceZero

)

{
    if (complianceZero < 0)
    {
        logger(ERROR, "complianceZero(%) argument should be non-negative!", complianceZero);
    }
    complianceZero_ = complianceZero;
}

References complianceZero_, ERROR, and logger.

setConstantC1()

void SinterNormalSpecies::setConstantC1

(

Mdouble

constantC1_

)

{
    if (complianceOne < 0)
    {
        logger(ERROR, "ComplianceOne(%) argument should be non-negative!", complianceOne);
    }
    constantC1_ = complianceOne;
}

References constantC1_, ERROR, and logger.

setDissipation()

void SinterNormalSpecies::setDissipation

(

Mdouble

dissipation

)

Sets the linear dissipation coefficient of the linear plastic-viscoelastic normal force.

should be non-negative

Parameters

[in]

dissipation

the linear dissipation coefficient of the linear plastic-viscoelastic normal force.

{
    if (dissipation < 0)
    {
        logger(ERROR, "setDissipation(%) argument should be non-negative!", dissipation);
    }
    dissipation_ = dissipation;
}

References dissipation_, ERROR, and logger.

Referenced by setLoadingStiffnessAndDissipation().

setInverseSinterViscosity()

void SinterNormalSpecies::setInverseSinterViscosity

(

Mdouble

inverseSinterViscosity

)

Sets inverseSinterViscosity_.

should be non-negative

Parameters

[in]

the

linear dissipation coefficient of the linear plastic-viscoelastic normal force.

{
    //assertOrDie(inverseSinterViscosity < 0, "inverseSinterViscosity should be non-negative!");
    if (inverseSinterViscosity < 0)
    {
        logger(ERROR, "setInverseSinterViscosity(%) argument should be non-negative!", inverseSinterViscosity);
    }
    setSinterType(SINTERTYPE::PARHAMI_MCKEEPING);
    inverseSinterViscosity_ = inverseSinterViscosity;
}

References ERROR, inverseSinterViscosity_, logger, PARHAMI_MCKEEPING, and setSinterType().

Referenced by setParhamiMcKeeping(), and setSinterForceAndTime().

setLoadingStiffness()

void SinterNormalSpecies::setLoadingStiffness

(

Mdouble

loadingStiffness

)

Sets the loading stiffness of the linear plastic-viscoelastic normal force.

Parameters

[in]

loadingStiffness

the loading stiffness of the linear plastic-viscoelastic normal force.

{
    loadingStiffness_ = loadingStiffness;
}

References loadingStiffness_.

Referenced by setLoadingStiffnessAndDissipation(), and setPlasticParameters().

setLoadingStiffnessAndDissipation()

void SinterNormalSpecies::setLoadingStiffnessAndDissipation

(

helpers::KAndDisp

new_

)

Allows the spring and dissipation constants to be changed simultaneously.

Parameters

[in]

new_

a helper struct containing both the loading stiffness and the disssipation coefficient.

{
    setLoadingStiffness(new_.k);
    setDissipation(new_.disp);
}

References helpers::KAndDisp::disp, helpers::KAndDisp::k, setDissipation(), and setLoadingStiffness().

setParhamiMcKeeping()

void SinterNormalSpecies::setParhamiMcKeeping	(	Mdouble	alpha,
		Mdouble	beta,
		Mdouble	atomicVolume,
		Mdouble	surfaceEnergy,
		Mdouble	thicknessDiffusion,
		Mdouble	activationEnergy,
		Mdouble	temperature
	)

Sets the sinterAdhesion_ and inverseSinterViscosity_ based on the Parhami-McKeeping parameters.

should be non-negative

Parameters

[in]

the

linear dissipation coefficient of the linear plastic-viscoelastic normal force.

{
    setSinterType(SINTERTYPE::PARHAMI_MCKEEPING);
    const Mdouble boltzmannConstant /*k_B*/ = 1.38064852e-23;
    const Mdouble gasConstant /*R_g*/ = 8.314459848;
    const Mdouble thicknessDiffusionVacancy /*DB*/ =
            thicknessDiffusion * exp(-activationEnergy / gasConstant / temperature);
    const Mdouble diffusionParameter /*DeltaB*/ =
            atomicVolume / boltzmannConstant / temperature * thicknessDiffusionVacancy;
    setInverseSinterViscosity(constants::pi / (2.0 * beta * diffusionParameter));
    setSinterAdhesion(alpha / beta * constants::pi * surfaceEnergy);
    logger(INFO,
           "Set sintering parameters: the adhesion force f_a=%*r, the rate of change of the plastic overlap is d(delta0)/dt=f_ep/(%*a^4)",
           getSinterAdhesion(),
           getInverseSinterViscosity());
}

References mathsFunc::beta(), mathsFunc::exp(), getInverseSinterViscosity(), getSinterAdhesion(), INFO, logger, PARHAMI_MCKEEPING, constants::pi, setInverseSinterViscosity(), setSinterAdhesion(), and setSinterType().

setPenetrationDepthMax()

void SinterNormalSpecies::setPenetrationDepthMax

(

Mdouble

penetrationDepthMax

)

Sets the maximum penetration depth of the linear plastic-viscoelastic normal force.

Parameters

[in]

penetrationDepthMax

the maximum penetration depth of the linear plastic-viscoelastic normal force.

{
    penetrationDepthMax_ = penetrationDepthMax;
}

References penetrationDepthMax_.

Referenced by setPlasticParameters().

setPlasticParameters()

void SinterNormalSpecies::setPlasticParameters	(	Mdouble	loadingStiffness,
		Mdouble	unloadingStiffnessMax,
		Mdouble	cohesionStiffness,
		Mdouble	penetrationDepthMax
	)

Sets all parameters of the linear plastic-viscoelastic normal force at once.

Parameters

[in]	loadingStiffness	the loading stiffness of the linear plastic-viscoelastic normal force.
[in]	unloadingStiffnessMax	the maximum unloading stiffness of the linear plastic-viscoelastic normal force.
[in]	cohesionStiffness	the cohesive stiffness of the linear plastic-viscoelastic normal force.
[in]	penetrationDepthMax	the maximum penetration depth of the linear plastic-viscoelastic normal force.

{
    if (loadingStiffness <= 0 || unloadingStiffnessMax < loadingStiffness || cohesionStiffness < 0 ||
        penetrationDepthMax < 0)
    {
        logger(ERROR, "arguments of setPlasticParameters do not make sense");
    }
    setLoadingStiffness(loadingStiffness);
    setUnloadingStiffnessMax(unloadingStiffnessMax);
    setCohesionStiffness(cohesionStiffness);
    setPenetrationDepthMax(penetrationDepthMax);
}

References ERROR, logger, setCohesionStiffness(), setLoadingStiffness(), setPenetrationDepthMax(), and setUnloadingStiffnessMax().

setSeparationDis()

void SinterNormalSpecies::setSeparationDis

(

Mdouble

separationDis

)

{
    if (separationDis < 0)
    {
        logger(ERROR, "SeparationDis(%) argument should be non-negative!", separationDis);
    }
    separationDis_ = separationDis;
}

References ERROR, logger, and separationDis_.

setSinterAdhesion()

void SinterNormalSpecies::setSinterAdhesion

(

Mdouble

sinterAdhesion

)

Sets sinterAdhesion_.

should be non-negative

Parameters

[in]

sinterAdhesion_

{
    if (sinterAdhesion < 0)
    {
        logger(ERROR, "setSinterAdhesion(%) argument should be non-negative!", sinterAdhesion);
    }
    sinterAdhesion_ = sinterAdhesion;
}

References ERROR, logger, and sinterAdhesion_.

Referenced by setParhamiMcKeeping(), and setSinterForceAndTime().

setSinterForceAndTime()

void SinterNormalSpecies::setSinterForceAndTime	(	Mdouble	adhesionForce,
		Mdouble	sinterTime,
		Mdouble	radius
	)

Todo:

fix

{
    sinterType_ = SINTERTYPE::PARHAMI_MCKEEPING;
    setSinterAdhesion(adhesionForce / radius);
    setInverseSinterViscosity(1.0 / (93.75 * adhesionForce * sinterTime / std::pow(radius, 5)));
    logger(INFO, "Set sintering parameters: adhesion force f_a=%*r,  sinter viscosity is nu = contactRadius^4/%",
           getSinterAdhesion(), getInverseSinterViscosity());
}

References getInverseSinterViscosity(), getSinterAdhesion(), INFO, logger, PARHAMI_MCKEEPING, setInverseSinterViscosity(), setSinterAdhesion(), and sinterType_.

setSinterRate()

void SinterNormalSpecies::setSinterRate

(

Mdouble

sinterRate

)

Sets sinterRate_.

should be non-negative

Parameters

[in]

sinterAdhesion_

{
    if (sinterRate < 0)
    {
        logger(ERROR, "setSinterRate(%) argument should be non-negative!", sinterRate);
    }
    sinterRate_ = sinterRate;
}

References ERROR, logger, and sinterRate_.

setSinterType()

void SinterNormalSpecies::setSinterType

(

SINTERTYPE

sinterType

)

Sets sinterRate_.

should be non-negative

Parameters

[in]

sinterAdhesion_

{
    sinterType_ = sinterType;
    if (sinterType_ == SINTERTYPE::CONSTANT_RATE)
        logger(INFO, "Sintertype set to CONSTANT_RATE");
    else if (sinterType_ == SINTERTYPE::PARHAMI_MCKEEPING)
        logger(INFO, "Sintertype set to PARHAMI_MCKEEPING");
    else if (sinterType_ == SINTERTYPE::TEMPERATURE_DEPENDENT_FRENKEL)
        logger(INFO, "Sintertype set to TEMPERATURE_DEPENDENT_FRENKEL");
    else if (sinterType_ == SINTERTYPE::REGIME_SINTERING)
        logger(INFO, "Sintertype set to REGIME_SINTERING");
    else
        logger(ERROR, "Sintertype not understood");
}

References CONSTANT_RATE, ERROR, INFO, logger, PARHAMI_MCKEEPING, REGIME_SINTERING, sinterType_, and TEMPERATURE_DEPENDENT_FRENKEL.

Referenced by setInverseSinterViscosity(), and setParhamiMcKeeping().

setStiffnessAndRestitutionCoefficient()

void SinterNormalSpecies::setStiffnessAndRestitutionCoefficient	(	Mdouble	stiffness,
		Mdouble	eps,
		Mdouble	mass
	)

Sets k, disp such that it matches a given tc and eps for a collision of two copies of P.

Sets k, disp such that it matches a given tc and eps for a collision of two copies of P

Parameters

[in]	stiffness	stiffness
[in]	eps	restitution coefficient
[in]	mass	effective particle mass, \(\frac{2}{1/m1+1/m2}\)

{
    loadingStiffness_ = stiffness;
    if (eps == 0.0)
    {
        dissipation_ = std::sqrt(2.0 * mass * stiffness);
    }
    else
    {
        dissipation_ =
                -std::sqrt(2.0 * mass * stiffness / (constants::sqr_pi + mathsFunc::square(log(eps)))) * log(eps);
    }
    unloadingStiffnessMax_ = loadingStiffness_;
}

References dissipation_, loadingStiffness_, mathsFunc::log(), constants::sqr_pi, mathsFunc::square(), and unloadingStiffnessMax_.

setSurfTension()

void SinterNormalSpecies::setSurfTension

(

Mdouble

complianceZero

)

{
    if (surfTension < 0)
    {
        logger(ERROR, "SurfTension(%) argument should be non-negative!", surfTension);
    }
    surfTension_ = surfTension;
}

References ERROR, logger, and surfTension_.

setTemperatureDependentSinterRate()

void SinterNormalSpecies::setTemperatureDependentSinterRate

(

std::function< double(double temperature)>

temperatureDependentSinterRate

)

{
    temperatureDependentSinterRate_ = temperatureDependentSinterRate;
}

References temperatureDependentSinterRate_.

setUnloadingStiffnessMax()

void SinterNormalSpecies::setUnloadingStiffnessMax

(

Mdouble

unloadingStiffnessMax

)

Sets the maximum unloading stiffness of the linear plastic-viscoelastic normal force.

Parameters

[in]

unloadingStiffnessMax

the maximum unloading stiffness of the linear plastic-viscoelastic normal force.

{
    unloadingStiffnessMax_ = unloadingStiffnessMax;
}

References unloadingStiffnessMax_.

Referenced by setPlasticParameters().

write()

void SinterNormalSpecies::write

(

std::ostream &

os

)

const

Writes the species properties to an output stream.

Parameters

[out]

output

stream (typically the restart file)

{
    os << " loadingStiffness " << loadingStiffness_;
    os << " maxUnloadingStiffness " << unloadingStiffnessMax_;
    os << " cohesionStiffness " << cohesionStiffness_;
    os << " maxPenetration " << penetrationDepthMax_;
    os << " dissipation " << dissipation_;
    os << " sinterAdhesion " << sinterAdhesion_;
    os << " inverseSinterViscosity " << inverseSinterViscosity_;
    os << " sinterRate " << sinterRate_;
    os << " complianceZero " << complianceZero_;
    os << " surfTension " << surfTension_;
    os << " constantC1 " << constantC1_;
    os << " separationDis " << separationDis_;
    os << " sinterType " << (unsigned) sinterType_;
}

References cohesionStiffness_, complianceZero_, constantC1_, dissipation_, inverseSinterViscosity_, loadingStiffness_, penetrationDepthMax_, separationDis_, sinterAdhesion_, sinterRate_, sinterType_, surfTension_, and unloadingStiffnessMax_.

Member Data Documentation

cohesionStiffness_

Mdouble SinterNormalSpecies::cohesionStiffness_

private

the adhesive spring constant (k^c) for plastic deformations

Referenced by getCohesionStiffness(), mix(), read(), setCohesionStiffness(), SinterNormalSpecies(), and write().

complianceZero_

Mdouble SinterNormalSpecies::complianceZero_

private

Compliance 0, C_0, corresponds to the inverse of stiffness at the instantaneous time.

Referenced by getComplianceZero(), mix(), read(), setComplianceZero(), SinterNormalSpecies(), and write().

constantC1_

Mdouble SinterNormalSpecies::constantC1_

private

Material constant

Referenced by getConstantC1(), mix(), read(), setConstantC1(), SinterNormalSpecies(), and write().

dissipation_

Mdouble SinterNormalSpecies::dissipation_

private

linear dissipation coefficient

Referenced by computeTimeStep(), getCollisionTime(), getDissipation(), mix(), read(), setCollisionTimeAndRestitutionCoefficient(), setDissipation(), setStiffnessAndRestitutionCoefficient(), SinterNormalSpecies(), and write().

inverseSinterViscosity_

Mdouble SinterNormalSpecies::inverseSinterViscosity_

private

Determines sinter viscosity nu = contactRadius^4/inverseSinterViscosity_ in sinter rate: d(delta0)/dt = (fa+fep)/nu

Referenced by getInverseSinterViscosity(), mix(), read(), setInverseSinterViscosity(), SinterNormalSpecies(), and write().

loadingStiffness_

Mdouble SinterNormalSpecies::loadingStiffness_

private

(normal) spring constant (k_1)

Referenced by getCollisionTime(), getLoadingStiffness(), mix(), read(), setCollisionTimeAndRestitutionCoefficient(), setLoadingStiffness(), setStiffnessAndRestitutionCoefficient(), SinterNormalSpecies(), and write().

penetrationDepthMax_

Mdouble SinterNormalSpecies::penetrationDepthMax_

private

the depth (relative to the normalized radius) at which k_2^max is used (phi_f)

Referenced by getPenetrationDepthMax(), mix(), read(), setPenetrationDepthMax(), SinterNormalSpecies(), and write().

separationDis_

Mdouble SinterNormalSpecies::separationDis_

private

Separation distance comes from the fracture theory.

Referenced by getSeparationDis(), mix(), read(), setSeparationDis(), SinterNormalSpecies(), and write().

sinterAdhesion_

Mdouble SinterNormalSpecies::sinterAdhesion_

private

Determines sinter adhesion force fa=sinterAdhesion_*radius in sinter rate: d(delta0)/dt = (fa+fep)/nu

Referenced by getSinterAdhesion(), mix(), read(), setSinterAdhesion(), SinterNormalSpecies(), and write().

sinterRate_

Mdouble SinterNormalSpecies::sinterRate_

private

Determines sinter rate: d(delta0)/dt = (fa+fep)/nu

Referenced by getSinterRate(), read(), setSinterRate(), SinterNormalSpecies(), and write().

sinterType_

SINTERTYPE SinterNormalSpecies::sinterType_

private

sinterType options determin how the rate of sintering, d(equilibriumOverlap)/dt is computed PARHAMI_MCKEEPING: sinter rate given by (sinterAdhesion+normalForce)/sinterViscosity CONSTANT_RATE: sinter rate given by sinterRate

Referenced by getSinterType(), read(), setSinterForceAndTime(), setSinterType(), SinterNormalSpecies(), and write().

surfTension_

Mdouble SinterNormalSpecies::surfTension_

private

Material constant

Referenced by getSurfTension(), mix(), read(), setSurfTension(), SinterNormalSpecies(), and write().

temperatureDependentSinterRate_

std::function<double(double temperature)> SinterNormalSpecies::temperatureDependentSinterRate_

private

Initial value:

= [this](
            double temperature) { return sinterRate_; }

Referenced by getTemperatureDependentSinterRate(), and setTemperatureDependentSinterRate().

unloadingStiffnessMax_

Mdouble SinterNormalSpecies::unloadingStiffnessMax_

private

the maximum elastic constant (k_2^max) for plastic deformations

Referenced by computeTimeStep(), getUnloadingStiffnessMax(), mix(), read(), setCollisionTimeAndRestitutionCoefficient(), setStiffnessAndRestitutionCoefficient(), setUnloadingStiffnessMax(), SinterNormalSpecies(), and write().

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

• SinterNormalSpecies.h
• SinterNormalSpecies.cc