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jason.ryon April 29, 2010 09:43

polynomial thermophysical properties
I am looking for an example of how to use the hpolynomialThermo and polynomialTransport in the thermophysicalProperties file for rhoPisoFoam.

I have played a little with the other types (sutherlands, hconst, etc...) but I can't figure out what the syntax for the polynomial type. Unfortunately the User guide isn't very helpful, and I can't find any similar examples.

For example, I want to have air and I know the 7-coefficient polynomial for mu and kappa with polynomialTransport, but I try:

thermoType hPsiThermo<pureMixture<polynomialTransport<specieT hermo<hpolynomialThermo<perfectGas>>>>>;
mixture //keyword
air 1 28.966 //species
1003.82 0 //hConstantThermo
0.1 0.2 0.3 0.4 0.5 0.6 0.7; //this is the polynomial for mu
0.1 0.2 0.3 0.4 0.5 0.6 0.7; //this is the polynomial for kappa

but it gives a error about unknown basicPsiThermo type.

Do I have to do something to enable the polynomialTransport and hpolynomialThermo types for this solver (rhoPisoFoam)? Could somebody please proved an example for me?


Chris Lucas May 4, 2010 04:09

Hi Jason,

the reason why you can't use this combination of material modells is because this combination isn't defined in OF1.6.

Maybe it is not possible do uses this models together. If you want to try it anyway, have a look at the following files.





jabecker May 11, 2011 06:16

thermophysicalProperties: using polynomialTransport and sutherlandTransport

I was wondering if you ever found a solution for this. I am working in buoyantPimpleFoam and my thermophyicalProperties file looks like this:

thermoType hRhoThermo<pureMixture<polynomialTransport<specieT hermo<hConstThermo<perfectGas>>>>>;

mixture air 1 28.9 1000 0
-2e-11 6e-08 3e-06 //mu
-3e-08 9e-05 0.0017; //thermal conductivity

pRef 100000;

When I run it however, I get the following error:

Unknown basicRhoThermo type hRhoThermo<pureMixture<polynomialTransport<specieT hermo<hConstThermo<perfectGas>>>>>

Valid basicRhoThermo types are:

hRhoThermo<pureMixture<constTransport<specieThermo <hConstThermo<perfectGas>>>>>
hRhoThermo<pureMixture<sutherlandTransport<specieT hermo<hConstThermo<perfectGas>>>>>
hRhoThermo<pureMixture<sutherlandTransport<specieT hermo<janafThermo<perfectGas>>>>>
hsRhoThermo<pureMixture<constTransport<specieTherm o<hConstThermo<perfectGas>>>>>
hsRhoThermo<pureMixture<sutherlandTransport<specie Thermo<hConstThermo<perfectGas>>>>>
hsRhoThermo<pureMixture<sutherlandTransport<specie Thermo<janafThermo<perfectGas>>>>>

From function basicRhoThermo::New(const fvMesh&)
in file rhoThermo/basicRhoThermo/newBasicRhoThermo.C at line 66.

FOAM exiting

From my understanding it basically it says that if I use hRhoThermo then I cannot use polynomialTransport:confused: Quick question as well, is my format for inserting the polynomial coefficients correct? The user guide provides no examples and I could not find anything on the forum. For example, my equation for mu is:

-2e-11 x^2 + 6e-08 x + 3e-06 = y

So I inserted it as just:

-2e-11 6e-08 3e-06 //mu

Is that right? Also, is it correct to put the values for mu and then kappa or is there a special format that tells OpenFoam how many constants to expect etc?

One last thing, when you use sutherlandTransport, does the temperature dependent viscosity (mu) lead to a temperature dependent thermal conductivity (kappa)? I am wanting to change the kappa to be temperature dependent, but it seems that polynomialTransport is the only way to accomplish this.

Again, any help would be greatly appreciated. Thank you in advance for your replies:D


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