Dear all, now I’m doing a simluation with second-order moments model. And I try to do a liquid-solid two phase flow simulation. However, I found it didn’t converge as DT was increasingly smaller. I tried to reduce the number of grid. It didn’t work.And the model can be executed with gas-solid simulation. So I wanna know whether there is a way to solve this problem.Thanks all.
Moment method to do some population balance modeling? Please provide more information about your problem, and post your files here.
Dear Gao,
Firstly, thanks for your reply. The second order moments model is an anisotropic model, which is different from kinetic theory of granular flow (isotropic). Now the biggest problem is that it didn’t converge when I change gas into liquid as fluid phase (Only changing the fluid’s density). So,I wanna find a solution about it. Thanks for you again.
Why not also change fluid viscosity as liquid viscosity is ~100 times of the gas viscosity. Also larger viscosity can helps converge. Try fist-order discretization to get a better initial fluid field and then switch to second-order.
Thank for you again, Gao. Actually, I have tried to change the parameter of fluid. Including viscosity, density etc. And now I’m busy on a normal fluidized bed simulation without second-order moment. It can be worked.
So, Gao,Do you know any method to help simulation converge in liquid-solid bed(such as grid)? Looking forward to your reply.
You might need to check your implementation of the SOM model as the model diverges only after changing the fluid properties. You may also test the model by changing the viscosity and density moderately (10, 100, then 1000 times).
Very grateful for you, Gao. I’ll try to change the viscosity and density of fluid step by step. By the way, Could you explain the meaning of ’ check your implementation of the SOM model’ to me. Thanks a lot.
I mean double check your second order moment model if it still can not converge after you tried all attempts.