Development of Wall Injection Model for Solid Rocket Motor Internal Flow by Block-Structure Cartesian Mesh

Few researchers have addressed the problem of wall boundaries realistically in the case of solid rocket motor internal flow analysis. The aim of this study is to develop a wall injection model using the immersed boundary method. Furthermore, we investigated the effect of the wall injection mass flow rate using the BCM solver included in this model. The numerical model of validation is a 1/30th-scale modular axisymmetric model of the Arian 5 SRM. First, we validated the propellant wall injection model and clarified the mesh convergence. From the validation results and mesh sensitivity results, the analysis results of the present study using fine mesh have the same analysis accuracy as those of Anthoine et al. Next, we investigated the effects of the wall injection mass flow rate in SRM combustors for three different types of wall injection conditions (e.g., flow type 1, flow type 2, and flow type 3). The comparison between flow type 2 and flow type 1 indicates that the flow field in the propellant wall zone becomes complex in the case of flow type 2. In the case of flow type 2, vortices are generated at the boundary between the high Mach number region and low Mach number region.