[chenghui62000]

Dear all,

I am trying to compile a solver from OF301 to OF1812 and encountered an error in the code.

The error are like that:

multiStepNetPorosityZone/multiStepNetPorosityZone.C: In member function ‘Foam::tmp<Foam::fvMatrix<Foam::Vector<double> > > Foam::multiStepNetPorosityZone::ddt(Foam::volScalarField&, Foam::volVectorField&) const’:
multiStepNetPorosityZone/multiStepNetPorosityZone.C:202:19: error: binding reference of type ‘Foam::fvVectorMatrix& {aka Foam::fvMatrix<Foam::Vector<double> >&}’ to ‘const Foam::fvMatrix<Foam::Vector<double> >’ discards qualifiers
     modifyddt(tres());
               ~~~~^~
multiStepNetPorosityZone/multiStepNetPorosityZone.C:51:6: note:   initializing argument 1 of ‘void Foam::multiStepNetPorosityZone::modifyddt(Foam::fvVectorMatrix&) const’
 void Foam::multiStepNetPorosityZone::modifyddt(fvVectorMatrix& m) const
      ^~~~
/opt/OpenFOAM/OpenFOAM-v1812/wmake/rules/General/transform:34: recipe for target 'Make/linux64GccDPInt32Opt/multiStepNetPorosityZone/multiStepNetPorosityZone.o' failed

The relevant source code is liked:

//- modify ddt term
void Foam::multiStepNetPorosityZone::modifyddt(fvVectorMatrix& m) const
{
    const labelList& cells = mesh_.cellZones()[porosityZoneID_];
    const scalar coeff((1.0+addedMassCoeff_*(1-porosity_)/porosity_)/porosity_);
    forAll(cells, i)
    {
        m.diag()[cells[i]]   *= coeff;
        m.source()[cells[i]] *= coeff;
    }
}

Foam::tmp<Foam::fvVectorMatrix> 
Foam::multiStepNetPorosityZone::ddt(volScalarField& rho, volVectorField& U) const
{
    tmp<fvVectorMatrix> tres = fvm::ddt(rho,U);
    modifyddt(tres());
    return tres;
}

Could anyone help me with that?