It is well known that the characteristic Mach number (M), the ratio of the reference constant velocity to the constant magnitude of the speed of sound, is the main dimensionless parameter which characterizes the effects of compressibility in the problem of the flow of a Newtonian fluid. Indeed, in the investigation of the flow of a compressible fluid, much of the analysis is considered in terms of the Mach number, and four cases are usually studied, namely subsonic (M < 1), transonic (M \01 1), supersonic (M > 1) and hypersonic (M \02 1).