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wernsen April 3, 2012 09:12

ThermophysicalProperties
 
Hey guys,

I am having troubles to figure out what the Hf-Value in the thermodynamics is. In the doc of OF:

Code:

air
{
    specie
    {
        nMoles          1;
        molWeight      28.96;
    }
    thermodynamics
    {
        Cp              1004.5;
        Hf              2.544e+06;
    }
    transport
    {
        mu              1.8e-05;
        Pr              0.7;
    }
}

so Air has 2.544e+6. The doc says it is the heat of fusion. -> I AM CONFUSED

Tim.WA September 8, 2012 11:09

Bump!

I'm also quite confused about this, all the tutorial examples I can find that are supposedly air have Hf set to 0.

any clues anyone?

Tim.WA September 9, 2012 08:56

Ok think I cracked it for anyone who comes along, Hf is a reference heat of fusion - I was looking in the source code hConstThermoI.h and it's only used to define enthalpy

h = cp*T + Hf

hence only applies with multiple phases or fluid types since h = cp*T generally
therefore if using a single fluid type it doesn't matter what you set it to

please correct me if I'm wrong :-)


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