[sarahtuvia]

Hi everyone
How is the total temperature calculated in star-ccm ?
thanks
tuvia

[ashokac7]

Total temperature makes sense only for the flow with Mach>0.5. For in-compressible fluids as Gamma (Cp/Cv)m is 1, Total temperature equals static temperature
These are 2 formualtions used by Star-CCM for total temperature.

total temp1.PNG

total temp2.PNG

Keep in mind that there use is conditional. Like second formulation holds true for isotropic conditions.

[sarahtuvia]

Thank you, Ashock. It helped

[sarahtuvia]

Hi Ashock
I've noticed that even at high supersonic flow starccm uses the first formula

Tt=Ts + v**2/2/Cp

I'd like to use the second formula

Tt=Ts*(1+(gamma-1)/2*Mach**)

but I do not know how to insert the value of Gamma Do you have any idea ?

[ashokac7]

Originally Posted by sarahtuvia

Hi Ashock
I've noticed that even at high supersonic flow starccm uses the first formula

Tt=Ts + v**2/2/Cp

I'd like to use the second formula

Tt=Ts*(1+(gamma-1)/2*Mach**)

but I do not know how to insert the value of Gamma Do you have any idea ?

Yes. You can create a field function with this definition.
create a field function and put this definition.

(${Temperature})*(1+(${Ma}*${Ma}*(1.4-1))/2)

you can copy paste this directly. Change Gamma from 1.4 to your choice.

For ${Ma},
You have to create mass flow average (or area average) report, rename it as Ma, select part/section and field function as mach number.

Or else You can directly use Mach number filed function in field function definition, but I was getting some error, that is why I created report with Mach number definition.

[sarahtuvia]

Thank you Ashock