Multidisciplinary Design Sensitivity Analysis of a Spacecraft Monopropellant Propulsion system by Latin Hypercube Sampling (LHS)

Accurate solving of complex systems such as space systems and specifically space propulsion system is very costly and time consuming. By developing and building a surrogate model, the solution time and the cost can be reduced. The closer the surrogate model is to the actual model, the more accurate the solution and the lower the error rate. High-precision successor models are called metamodels. The basis of producing a high-precision meta-model is to perform high-precision sensitivity analysis with a suitable method. Sensitivity analysis can show the effect of input variables on output variables and produce a surrogate model by eliminating ineffective input variables. Therefore, sensitivity analysis is of great value in solving complex systems. The purpose of this paper is to analyze the sensitivity of the multidisciplinary design of a monopropellant liquid propulsion system by the Latin Hypercube Sampling method. In this article, the topics related to the liquid monopropellant propulsion system are divided into six parts: High pressure gas tank, liquid fuel tank, injector, decomposition chamber, catalytic bed and nozzle. By determining the input and output variables of each subject, the results of sensitivity analysis are displayed in two ways: the sensitivity of the input variables to the output and the two-by-two correlation of the parameters with each other. In the results, as can be seen, the specific impulse input variable, in the high-pressure gas tank and the liquid fuel tank, has no effect on the output variables. In the injector, the number of grooves, groove angles and fuel tank pressure do not have a significant effect on the output variables. In the decomposition chamber sensitivity analysis diagram, the radius of the granule and for the catalyst bed, in addition to the radius of the granule, the percentage of ammonia decomposition are also ineffective. Finally, the sensitivity analysis for the nozzle shows that the ratio of specific heat has no effect on the output variables.