#include <generalised_newtonian_constitutive_models.h>

Inheritance diagram for oomph::NicosConstitutiveEquation< DIM >:

Public Member Functions
	NicosConstitutiveEquation (double mu_inf_pt, double mu_0_pt, double *alpha_pt)

double	viscosity (const double &second_invariant_of_rate_of_strain_tensor)

double	dviscosity_dinvariant (const double &second_invariant_of_rate_of_strain_tensor)

Public Member Functions inherited from oomph::GeneralisedNewtonianConstitutiveEquation< DIM >
	GeneralisedNewtonianConstitutiveEquation ()
	Empty constructor. More...

virtual	~GeneralisedNewtonianConstitutiveEquation ()
	Empty virtual destructor. More...

Private Attributes
double *	Mu_inf_pt
	high shear rate viscosity More...

double *	Mu_0_pt
	zero shear rate viscosity More...

double *	Alpha_pt
	parameter that controls the steepness of the curve More...

Detailed Description

template<unsigned DIM>
class oomph::NicosConstitutiveEquation< DIM >

A GeneralisedNewtonianConstitutiveEquation class defining an arbitrary shear-thinning fluid

Constructor & Destructor Documentation

◆ NicosConstitutiveEquation()

template<unsigned DIM>

oomph::NicosConstitutiveEquation< DIM >::NicosConstitutiveEquation	(	double *	mu_inf_pt,
		double *	mu_0_pt,
		double *	alpha_pt
	)

inline

       : GeneralisedNewtonianConstitutiveEquation<DIM>(),
         Mu_inf_pt(mu_inf_pt),
         Mu_0_pt(mu_0_pt),
         Alpha_pt(alpha_pt)
     {
     }

Member Function Documentation

◆ dviscosity_dinvariant()

template<unsigned DIM>

double oomph::NicosConstitutiveEquation< DIM >::dviscosity_dinvariant ( const double & second_invariant_of_rate_of_strain_tensor )

inlinevirtual

Function returning the derivative of the viscosity w.r.t. the second invariant of the rate of strain tensor For Newtonian behaviour this returns 0.0

Implements oomph::GeneralisedNewtonianConstitutiveEquation< DIM >.

     {
       // std::ostringstream error_stream;
       // error_stream << "This has not been implemented yet!";
       // throw OomphLibError(
       // error_stream.str(),
       // OOMPH_CURRENT_FUNCTION,
       // OOMPH_EXCEPTION_LOCATION);
  
       // return 0.0;
  
       return (*Alpha_pt) * ((*Mu_inf_pt) - (*Mu_0_pt)) *
              exp(-(*Alpha_pt) * second_invariant_of_rate_of_strain_tensor);
     }

References oomph::NicosConstitutiveEquation< DIM >::Alpha_pt, and Eigen::bfloat16_impl::exp().

◆ viscosity()

template<unsigned DIM>

double oomph::NicosConstitutiveEquation< DIM >::viscosity ( const double & second_invariant_of_rate_of_strain_tensor )

inlinevirtual

Function implementing the constitutive model Input: second invariant of the rate of strain Output: the viscosity For Newtonian behaviour this returns 1

Implements oomph::GeneralisedNewtonianConstitutiveEquation< DIM >.

     {
       return (*Mu_inf_pt) +
              ((*Mu_0_pt) - (*Mu_inf_pt)) *
                exp(-(*Alpha_pt) * second_invariant_of_rate_of_strain_tensor);
     }