A computing method for the simulation of non-steady state burning of solid propellants

Computer simulation of the non-steady state burning of solid propellants is achieved by the integration of the partial differential equation describing this phenomenon. The problem is of the parabolic type, with a moving boundary. A continuous-space-discrete-time approximation algorithm is applied to obtain differential-difference equations which can be solved sequentially. However, the integration of these equations cannot take place unless they are transformed to stable forms (from the computation point of view). Such a transformation is obtained by a method of decomposition which also takes care of the mixed boundary values problem. This new computing method is intended for hybrid computers, but can be implemented on digital computers. Results of a program on an IBM 7094 are shown. They have been found to be faster and more accurate than classical finite-differences methods previously used.