For flow over a Naca 0012 airfoil ( compressible)...I set a pressure far filed boundary condition. The inputs I have to give for this condition are mach number,gauge pressure and temperature...for example I give the guage pressure of 101325 pascal,temp of 300k and mach number of 0.4. How can I calculate the reynolds number for that case

It's easy. Initilize->Compute From, choose "Farfield", Fluent calculates automatically the velocity components. From that velocity, calculate Reynolds number!!!!!

ya I know...but the density and viscosity change...so the reynolds number is bit different...

for exmaple for this example in student fluent can u tell me how did he get 10 to power 5 the reynolds number

http://www.fluent.com/software/stude...al_airfoil.htm

Thanks

Ravi