Supersonic flow was a flow in which a Mach number is greater than 1.0, and this flow is very important in the
design of aircraft and rockets. During the past, the experimental and analytical methods were used to simulate the
properties of supersonic flow over a limited number of shapes, but for supersonic three-dimensional shapes such as a
3D arc circular bump, the analytical method was failed due to non-linearity also to design an aircraft many thousands of
tests were drawn in a supersonic wind tunnel which requires a hard and expensive work and require a very long time. In
contrast, a numerical prediction give the same result with a short-time and an accurate computation and the computer
program may be changed easily to deal with any other complex shape such as wing, airfoil and missile AL-Dulaimy
(2002) .In the numerical simulation, the complex differential equations are overcame by replacing it with differences,
calculated from a finite number of values associated with the computational nodes, which are distributed on a suitable
grid over the solution domain. In the present study, the predictor-corrector MacCormack’s explicit finite difference
method with time marching was adopted to predict the aerodynamic characteristics of three-dimensional external
compressible inviscid supersonic flow over an arc circular bump to compute the primitive variables such as the internal
energy, pressure, density, Mach number and temperature at each grid. The time- marching method was chosen to treat
an arc circular bump as a plane body. In the next section, the mathematical analysis will be described in detail and the
style, which used to produce meshes or grids are given. It is very important to refer that the primitive variable covers,
velocity, density, temperature, pressure, internal energy and Mach number.