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codyf May 24, 2011 14:42

Volume Integral on Solids

Under Results -> Reports -> Volume Integrals, when I do a Volume Integral using Density -> Density, I am getting zero mass for the two solids in my model. When I use Density -> "Density All" I get the correct masses for the solids (kg/m3*m3). I have two fluid and two sold zones in the model, the fluid zones calculate the same using either "Density" or "Density All" for the Field Variable.

The Minimum & Maximum "Density" for the solid zones also report to zero, but are non-zero for "Density All."

Really, I'd like to compute the Mass-Integral of Temperature -> Internal Energy (J/kg*kg/m3*m3), which also comes out zero for the two solid zones.

I have density, specific heat, and thermal conductivity defined for the solid material.

What am I missing?


codyf May 25, 2011 00:26

To follow up ...

The field variable documentation (33.4) says plots/reports of Density include fluid zones only, and of Density All include both fluid and solid zones.

I created a DEFINE_ON_DEMAND UDF to report the mass integral of enthalpy (sum of cell enthalpy*density*volume) that works for both solid and fluid zones. I'm not sure how internal energy is calculated; also, I get an access violation for cell pressure C_P(c,t) in the solid zone. I couldn't get "domain = Get_Domain(1)" and "Thread *t = Lookup_Thread(domain, id)" to work together within the same function, I finally used the format of the example in Domain Pointer of the UDF manual.

Another way to do it, I think, is to make the solid zone a fluid zone, and fix the x, y, z velocities to zero for the fluid zone under Cell Zone Conditions.

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