Learning Forum

[2018ugme092]

I am working on a simulation of a heterogeneous reaction between h2(g) and caso4(s), my simulation runs for some 5-7 time steps and then it gives "FLOATING POINT EXCEPTION".

Here is a screenshot of the console at floating point exception:

[Rob]

The limiter warning suggests the solver isn't happy. That you're also using 50 iterations to converge a time step is also a clue. TIme step is 1e-5s ?
Also, adjusting the UR factors in a transient run isn't really recommended, use default and reduce the time step. If you look at the flow speed and cell size how long does it take for the flow to cross a cell?

[2018ugme092]

Now we are using a step-size of 1e-10 and the initial 200 iterations don't give any message like "turbulent viscosity limited to viscosity ratio of 1.000000e+05 in xxxxx cells.."
but soon it starts to increase, after around 1000 time steps, the viscosity ratio problem reaches 200-210 cells and the number is still increasing with time steps.
I followed your recommendation of not changing the UR factors and maybe that helps slightly. However, I believe the problem still persists.

[Rob]

With that time step the solver may not see much change, so the model may be stable. What is the cell quality and mesh resolution like?