[piu58]

Dear Foamers,

I have to simulation the conditions of chemical reactions at a boundary layer (electrochemical deposits). One aspect of this is the mass transport to the boundary. Because this is not ready available in OpenFoam I used the temperature instead of the concentration. The equations are equal.

Doing this I have to give the thermal properties. I don't know the real values for my galvanic bath, so I started with the values of water. For reference I give my thermophysicalProperties file at the end of the post.
Unfortunately, this is only weak documented in the OF literature. I found out everything except "Hf", which I set to zero (as in examples I found). I switched it to 1000, but nothing happens (at least in my incompressible case with noc changes of the density).

Does anybody know what is this value for? Thank you in advance.

thermoType
{
    type            heRhoThermo;
    mixture         pureMixture;
    transport       const;
    thermo          hConst;
    equationOfState rhoConst;
    specie          specie;
    energy          sensibleEnthalpy;
}

mixture
{
    specie
    {
        nMoles          1; // not used, only necessary for gases
        molWeight       18; // ditto
    }
    equationOfState // rho(T)
    {
	// density
        rho             1000;
    }
    thermodynamics
    {
	// heat capacity
        Cp              4181;
	// ???
        Hf              0;
    }
    transport
    {	
	// dynamic  viscosity
        mu              959e-6;
	// Prandtl number: 13,44 (0 °C); 11,16 (5 °C); 6,99 (20 °C); 4,34 (40 °C); 3,00 (60 °C); 2,20 (80 °C); 1,75 (100 °C)
        Pr              6.62;
    }
}

[TobiF]

Hey,
as you can see in the link below (chapter 7.1.3) Hf is the heat of fusion

https://cfd.direct/openfoam/user-guide/thermophysical/

[piu58]

Thank you! Now it is clear that I don't need it.

[Bloerb]

Hf is the heat of fusion. It is however not used if sensibleEnthalpy or sensibleInternalEnergy is specified. This quantity only applies to totalEnthalpy etc. For example evaporation or combustion, melting and solidification need a heat of fusion. The same applies to nMoles and moleWeight. Those are only used if something beside a pureMixture is looked at. Like a mixture of two different gases. Nevertheless a value must be present. Which value is choosen does not affect your simulation results since it is not used to calculate any quantity.