cantera/src/transport/TortuosityMaxwell.cpp

105 lines
3.6 KiB
C++

/**
* @file TortuosityBase.cpp
* Base class to compute the increase in diffusive path length associated with
* tortuous path diffusion through, for example, porous media.
*/
/*
* Copyright (2005) Sandia Corporation. Under the terms of
* Contract DE-AC04-94AL85000 with Sandia Corporation, the
* U.S. Government retains certain rights in this software.
*/
/*
* $Revision: 572 $
* $Date: 2010-08-13 20:21:57 -0600 (Fri, 13 Aug 2010) $
*/
#include "TortuosityMaxwell.h"
#include "cantera/base/ctexceptions.h"
#include <string>
namespace Cantera
{
//====================================================================================================================
// Default constructor
TortuosityMaxwell::TortuosityMaxwell(doublereal relativeConductivities) :
TortuosityBase(),
relativeConductivities_(relativeConductivities)
{
}
//====================================================================================================================
// Copy Constructor
/*
* @param right Object to be copied
*/
TortuosityMaxwell::TortuosityMaxwell(const TortuosityMaxwell& right) :
TortuosityBase(),
relativeConductivities_(right.relativeConductivities_)
{
*this = right;
}
//====================================================================================================================
// Default destructor for TortuosityMaxwell
TortuosityMaxwell::~TortuosityMaxwell()
{
}
//====================================================================================================================
// Assignment operator
/*
* @param right Object to be copied
*/
TortuosityMaxwell& TortuosityMaxwell::operator=(const TortuosityMaxwell& right)
{
if (&right == this) {
return *this;
}
TortuosityBase::operator=(right);
relativeConductivities_ = right.relativeConductivities_;
return *this;
}
//====================================================================================================================
// Duplication operator
/*
* @return Returns a pointer to a duplicate of the current object given a
* base class pointer
*/
TortuosityBase* TortuosityMaxwell::duplMyselfAsTortuosityBase() const
{
TortuosityMaxwell* tb = new TortuosityMaxwell(*this);
return dynamic_cast<TortuosityBase*>(tb);
}
//====================================================================================================================
// The tortuosity factor models the effective increase in the diffusive transport length.
/*
* This method returns \f$ 1/\tau^2 \f$ in the description of the flux
*
* \f$ C_T D_i \nabla X_i / \tau^2 \f$.
*
*/
doublereal TortuosityMaxwell::tortuosityFactor(doublereal porosity)
{
return McMillanFactor(porosity) / porosity;
}
//====================================================================================================================
// The McMillan number is the ratio of the flux-like variable to the value it would have without porous flow.
/*
* The McMillan number combines the effect of toruosity
* and volume fraction of the transported phase. The net flux
* observed is then the product of the McMillan number and the
* non-porous transport rate. For a conductivity in a non-porous
* media, \f$ \kappa_0 \f$, the conductivity in the porous media
* would be \f$ \kappa = (\rm McMillan) \kappa_0 \f$.
*/
doublereal TortuosityMaxwell::McMillanFactor(doublereal porosity)
{
doublereal tmp = 1 + 3 * (1.0 - porosity) * (relativeConductivities_ - 1.0) / (relativeConductivities_ + 2);
return tmp;
}
//====================================================================================================================
}