Learning Forum

[abbas]

Hello,

 

I am simulating two-phase CO2 and I used a homogeneous equilibrium model. I used ANSYS AIM for creating the RGP table for both liquid and vapor CO2, so I believe that my RGP tables for both phases are fine and correct. There I haven't done any changes in RGP table. But even after 4500 iterations, I still receive the table bounds warnings in CFX.

How can I get rid of this warning?

[DrAmine]

By providing larger table bounds: during solution process variables might went outside of the range wherein the tables have been created. This might happen at the beginning and then disappear but not for this case. That is why check your case, boundary-conditions and perhaps enlarge the table bounds a bit to see if it is related to the tables or to the case setup itself.

[abbas]

I created the table for 2 Mpa to 15Mpa for pressure and 250K to350K for temperature. I know that the minimum pressure and temperature are inside the table because the inlet pressure is 12Mpa and 320K and the outlet is 6Mpa. I used the ANSYS AIM to generate the table. I think there shouldn't be a problem with RGP. But I am confused about why I have this warning.

 

Best regards

Abbas

[DrAmine]

I described the way I will debug the case. You have that warning either because during the solution process you are outside the range or the case is setup not properly or the table is not large enough.

Refer to the documentation (12.5.x) and check your inlet boundary and how you setup the fraction/enthalpy/temperature here.

 

Perhaps other community members might be helpful too. 

[NguyenLaTray311]

abbas,

Can you give some feedback whether you have resolved this issue? Also, you mentioned you used ANSYS AIM to generate the rgp table. Could you explain how you did it? I used NIST to RGP but it seems unreliable...

 

Thanks,

 

Nguyen