Effect of 3D Grain Design Uncertainties on Dual Thrust Solid Rocket Motor Performance

摘要

It is not desirable to use a rocket motor design if it is very sensitive to small geometric grain variations, which may result from many factors, such as manufacturing process error, in-service degradation or drift in operating conditions. These variations can cause optimized design to easily fall into sub-optimal regime. In present paper, a 3D grain configuration consisting of 3D finocyl geometry grain is optimized using hybrid optimization technique of Genetic Algorithm and Simulated Annealing to achieve dual thrust levels with given constrain and fixed motor envelope. In present paper, the uncertainties are set as percentages variation and their effects are examined for optimized design on motor performance for total impulse, propellant mass, average thrust ratio and maximum chamber pressure. Uniform Latin Hypercube Sampling is used to increase the design efficiency. The sensitivity analysis of the solution is done by Hadamard matrices approach and Monte Carlo simulation to evaluate the effects of uncertainties. It is shown that small variations in grain geometry can cause major deviation of expected motor performance parameters.