ICNPAA 2010: Mathematical Problems in
Engineering, Aerospace and Sciences

When the neutral burning characteristic with respect to time is needed in a mission, star grain geometry of solid propellant is used. Most of the grain regression is done by the geometric evolution analysis during its combustion. In this study, we present the comparison of the regression of two dimensional star grain geometry of a solid rocket motor by geometrical and numerical approach. In the geometric evolution technique, it is required to predefine the evolution zones to estimate the internal ballistics of the rocket motor before the grain regression occurs. But using the numerical method, no predefined zones are needed while it gives close result to that of the previous one. Both methods are based on the principle that burning will occur in the normal direction of the solid propellant surface.