Boundary conditions for free-field flame propagation
 

Can someone please explain the best way to set the boundary conditions for a free-field flame propagation simulation? All that I can find online are descriptions where an inflow is specified (or they do not apply for compressible, transient flow). However, in my case I want to simulate flame propagation in a wide and long tube, open at both ends .

I have tried several approaches in OpenFoam v3.0.1 (coalChemistryFoam), as well as with a previous employer but can never seem to get them correct. Right now I am just trying to complete a 1D simulation with outflow at both ends, but the result is dependent on how long I make the tube. One option is to make the pressure constant (by modifying the solver), but I would rather the low pressure fluctuation come out in the solution itself.

Any help, or references you could suggest that specifically look at compressible, transient flow with chemistry would be great. Also, any considerations needed once I move to turbulent flow (using RANS) would also be useful.

Thanks!

I was able to make progress on this later in the month.

See the post here for more information: http://www.cfd-online.com/Forums/ope...tml#post624884