Compressibility Effects on Dynamic Stall of an NACA 0012 Airfoil

D stall of an NACA 0012 airfoil for laminar flow conditions was studied by solving the compressible Navier Stokes equations in a body-fitted coordinate system. The compressibility effects on the dynamic stall were studied by computing the flow properties at Mach numbers 0.2 and 0.4 while freezing the chord Reynolds number and the reduced frequency at 5000 and 0.5, respectively. The numerical results indicate that compressibility has an inhibiting effect on the formation and growth of the leading-edge vortex. During the upstroke motion, prior to the formation of vortex, the lift and moment coefficients are consistently higher at the higher Mach number. Also, during the downstroke motion, the numerical results predict that the spilled vortex is convected downstream at a greater speed for the higher Mach number case.