Numerical Simulation And Analysis Of Dynamic Characteristics For Spacecraft Propulsion System

In this thesis, the dynamic characteristics and the fault characteristics of a ground experimental system for a certain spacecraft propulsion system were investigated using numerical simulation method.Firstly, the dynamics models of some main components for the experimental system are developed according to module-modeling and simulating method. The general simulation scheme which was consisted of component module, system module and solver module is proposed for system modeling and simulating.Secondly, the dynamic characteristics of the system were simulated and studied. The emphases of research work were put on the effect analysis of key factors to system dynamic characteristics, which include solenoid valve acting response time, combustion efficiency of chamber, pulse mode of thrusters, coupling operation of multi-thrusters, and so on. Based on simulation and theoretical analysis, a principle of multi-pipes subsection and constraint condition of integral step size in simulating computation was proposed.Finally, the characteristics of three common faults for spacecraft propulsion including propellant tank pressure fault, propellant leak and pipe blocked were simulated. Some qualitative features of three kinds of faults were obtained.The results of numerical simulation consist with ones of theoretic analysis and engineering practice. Meanwhile, it shows that the thesis' work and results are not only available for the designing and improving of spacecraft propulsion system, but also provide a good base for fault detection and diagnoses of the propulsion system.