i calculate a missile ranging from mach0.6 to mach 3, with the angle of attack 2 degree,4 degree,and 8 degree,the supersonic result(force coefficients and moment coefficients) is acceptable,but the subsonic result is far from the experimental data,who would please give me some advice on it,thanks fot regards now! k-e modle , steady, explicit multi-grid implemented inletressure-far-field outletressure out

Your are always going to battle with the coefficients in subsonic flow expecially the Cd numbers as the solution is domintaed by the viscous terms at low AoA

sorry,i have to add here that the supersonic results are not good too,30% lower than experimental data(for lift coefficient , 10% lower).the results are probably due to the difficulty to simulate fiction drag ,how can i deal with it? isn,t fluent good at dealing with it?