Learning Forum

[yijecho]

Hi all,

I am modeling a gas-porous solid reaction. When I used Volume-weighted-mixing-law for the mixture density, all the calculations went fine without any problems. But, when I switched it to Ideal-gas, the calculation stopped with a Floating point exception error. The residuals for the turbulence terms got increased with iterations. What would be solutions to this problem?

Thank you,

Yi Je

[DrAmine]

Much more conservative settings can be helpful like using smaller time scales and coupled pseudo-transient if steady.

[yijecho]

Thank you for your comment. I already used the coupled pseudo-transient setting. I have solved this problem by reducing the relaxation factor.

I wonder the reason why the ideal-gas mixing law caused the problem compared to the volume-averaged mixing law. I think the pressure and temperature terms in its density equation might affect the species transport to make the model more complicated. Would it be possible?

Best regards, Yije

[DrAmine]

Because you have now a pressure dependency for the density making the whole thing a bit stiff. Please mark as "Is Solved"