The Numerical Simulation Of The Thrust Vector Control System

Rocket engine is one kind of air jet engine that does not rely on outside air and bring propellant by itself according to the impulse principle.Energy is converted into kinetic energy in the rocket engine,and high speed jet stream comes from the rear of the nozzle to push the rocket.The direction of rocket engine is controlled by the thrust vector control system.This control system can also obtain controlling moment.The solid rocket motor nozzle in this paper which combines the thrust vector control system with the function to provide impetus for the rocket,is an improved axisymmetric vectoring exhaust nozzle.In consideration of the fact that the rocket engine nozzle works under the environment of high temperature and high pressure,suffering external force,the dynamic performance of the device is affected by comprehensive effect of various physical fields.So further analysis is needed to study the performance of the device.After a considerable study of literatures and monographs home and abroad,it is found that there are a few materials about fluid-thermal-solid field coupling analysis and most of them are incomplete.Besides rare researches focus on multi-field couplings of axisymmetric vectoring exhaust nozzle.One of the few studies could see some problems that motion analysis are incomplete,most of the models are two-dimensional design models,the results of flow field analysis is not ideal,or the results of coupling is not ideal.To solve the above problems,the article first introduced the fundamental theory of fluid-thermal-solid field coupling analysis.In the introduction,governing equations of fluid mechanics,heat transfer control equations and solid control equation are given.The chosen of turbulence model and solution process of CFD are also introduced.Next,the basic structure and working principle of primary member of the rocket engine nozzle have carried in detail,motion analysis are introduced.This system comprised two control methods,namely forward control and feedback control,which are also introduced.Finally,fluid field and thermal field of the combustion-gas stream in the nozzle have been analyzed by Fluent according to the given conditions.And on this basis,the aerodynamic load and the thermal load of combustion-gas flow are loaded into the solid by Ansys,then the fluid-thermal-solid field coupling analysis has been completed.According to the results of this analysis the feasibility of the configuration has been shown and it offers a theoretical basis for the optimum design of the device.