Psuedo Steady Simulations

Greg Perkins

Hi,

has anybody got experience with using commerical codes in a pseudo-steady mode?? By this I mean performing transient 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 using Fluent. 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. If I solve this as a fully coupled problem, then the coupling between reaction and flow restricts the time-step to low values. While this is rigourous it makes the simulations impractical - I am hoping to assume steady flow at each point in time to speed things up.

Many models have used this approach in the past, but none are reported within a commercial CFD code. Has anybody tried this or got any experience?????

Regards

Greg Perkins