Solid Rocket Motor Nozzle Optimization Design And Analysis Based On Coupled Field

Supersonic nozzle has played a role on turning subsonic airflow into supersonic airflow, so it is an essential component for rocket engine. As far as theory and engineering practice, it is a necessary study on carrying out the design optimization of solid rocket motor nozzle.The paper has three aspects of research work.Firstly, according to the general principles of nozzle design, asymmetrical supersonic solid rocket motor nozzle that exit Mach number is 3 has designed. Convergent curve uses the modified Vito Eric hinske formula, in addition, throat and expansion curve use 80% a Rao nozzle. The whole design process is made by Matlab programming to realize. At the same time, the Fluent has been used to simulate the internal static temperature and static pressure field. The results that exit Mach number is 2.59, which is roughly close to 3, has proved the feasibility of nozzle design.Secondly, the Fluent is used to simulate the influence on nozzle flow field if the nozzles design parameters(length of convergence, the initial Angle of expansion, contraction section shrink age ratio) change. We can obtain rules about the variation of the velocity and temperature fields when single factor changes. it makes a the optimal design of the nozzle design parameters by response surface methodology, which selects the initial Angle of expansion and contraction section shrink age ratio for two design variables, and the nozzle exit velocity for response value. When the shrinkage ratio is 1.82 and the initial expansion Angle is 19.94°, nozzle exit velocity is the largest maximum of 232 8.84m/s. Thrust has increased by 3.05% compared with optimization before.Finally, the appropriate insulation materials Zr O2 is choose to mitigate nozzle wall thermal deformation. In order to further illustrate the value of the insulation design, respectively, the Fluent simulate transient temperature field of existing or not thermal insulation wall, and the Ansys Workbench platform simulate structure deformation of nozzle of existing or not thermal insulation. It is show that nozzle tube wall temperature has fell by about 100℃ for the most high temperature and by about 50℃ for the low temperature place before, and that the maximum wall structure deformation decreased by about 6%.Therefore, it is important to choose proper thermal insulation material for mitigating the tube wall heat deformation.