Development of a hybrid method in a 3-D numerical burn-back analysis for solid propellant grains

This study was performed to analyze the performance of a solid propulsion system quickly and accurately. Systems that are currently in operation use a propellant with a complicated configuration to satisfy the performance requirements. Multi-dimensional internal ballistics analysis is essential in this case. The propellant's burning surfaces move in all directions, and the local burning velocity changes, so a 3-D analysis technique is necessary for the moving boundary. Previous research focused on improving the accuracy of the combustion configuration analysis using new methods, but it is difficult to apply them because user convenience was not considered. Therefore, the problems of the analysis methods were analyzed, and a hybrid burn-back analysis method was developed. The method's accuracy was improved by selectively using the minimum distance function (MDF) manipulation method, which has fast calculation speed, as well as a level set method for regions where the configuration of the propellant grains is complicated. The results verified that the accuracy was increased, and the calculation time was reduced.