How Does a Gurney Flap Enhance the Aerodynamics Forces?

CD = total drag coefficient CDa = drag coefficient associated with the acceleration of the wing CDm = drag coefficient associated with the motion of the wing CDs = drag coefficient associated with the surface vorticity and friction on the wing surface CDv = drag coefficient associated with to vorticity within the flowfield CL = total lift coefficient CLa = lift coefficient associated with the acceleration of the wing CLm = lift coefficient associated with the motion of the wing CLs = lift coefficient associated with the surface vorticity and friction on the wing surface CLv = lift coefficient associated with to vorticity within the flowfield c = chord length P = static fluid pressure Re = Reynolds number U max = maximum velocity u = velocity vector = air viscosity = air density = auxiliary potential function ! = vorticity