I am doing cfd simulations on missiles at different angles of attack. At higher angles of attack...alpha 30 and above...I experienced problems with trying to get the solutions to converge. Is this in anyway a reflection of the stability of the flowfield on the missile at those angles of attack? Can one use the fact that since something is not converging or is taking an extremely long time to converge as an indication that something is wrong with the way the problem is defined or that the solution itself is not stable?

Software being used: CFD-FASTRAN turbulence model: Menter-SST Thanks

high AOA flow tends to be unstable, flow is either periodic, aperiodic, chaotic or turbulent. Then you can not expect to converge to steady state in general cases.

Thanks versi. Another question: Are there any papers available that relate flow features to convergence?

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