A question about the volume fraction of a gas

MFiX How to
#1

Hi everyone, This is my case, the initial condition consists of 21.8%fluid(gas) and 78.2%solid2.When the calculation begins, the gas(reactant) enters from the bottom.This case involves a chemical reaction, which is an exothermic reaction.The initial temperature was 673.15K, but I observed from Paraview that after time step1, the temperature quickly dropped to 640K. I think this is not a mistake in the calculation of reaction heat. It may be because the initial gas in the reactor left quickly by top outlet, and the gas in the bottom entered slowly, so the volume fraction of the gas was less than 0.I have disabled close packing.But it still invalid.
ann-new.zip (32.0 MB)
Am I right in my guess? and how can I solve this problem?

#2

Sorry Chen, I’m not sure I completely understand … what do you mean “But it [is] still invalid” ?

#3

Hello @cgw ,I mean I try to disable close packing,but I still not solve the problem.