Improved Thrust Termination Modeling for Solid Rocket Motors

This effort addresses the need for a predictive model which characterizes the motor ejecta from thrust terminated and burn-to-depletion solid rocket motors. Two models will be developed: an engineering model that provides near term predictive capability and a high fidelity model which will provide guidance to improve the engineering models. The engineering model, developed under Phase I, will be extended, treating additional sources of debris and enfolding existing signature models for the validation phase of this effort. Predictions of solid motor performance and radar scene will be made for up to six flight tests for comparison to test data. Predictions will be made by coupling Sierra"s engineering model with a debris propagation and radar scene generation tool. Prior to the flight test predictions, Sierra will enhance its engineering model, including fragmentation predictions for charred internal insulation. A commercial system optimization tool set will be used to automate the analysis tool interactions, reducing the time required to achieve an acceptable solution. The detailed analysis tool effort will demonstrate a moving mesh capability applicable to the burning grain surface, demonstrate an improved rigid body (i.e. debris) model, and develop tools to import debris characteristics into the model.