Pseudo-Steady Simulations

Greg Perkins

Hi,

has anybody got any experience with using Fluent in a pseudo-steady mode?? By this I mean simulations in which you assume some equations are solved as steady (at each time-step) and some are solved as being fully transient.

I'm solving for a coal gasification reactor. In this case I'd like to assume steady gas flow (short residence time in my reactor) but still solve for transient heat flow and material balances. In this way I would hope to use large time-steps (say 2-10 mins) since I'm interested in dynamic peformance over long time frames.

Many models have used this approach in the past, but none are reported within a commercial CFD code. The scheme works in Fluent but I can't increase the time-step above about 1 second without stability problems. Has anybody tried this too?????

Regards

Greg Perkins