Design And Performance Simulation Of Solid Rocket Motor Nozzle

Nozzle is an important part of the thrust vector control system of solid rocket motor and high-performance design of a nozzle plays an important role in the performance of the motor. Aimed at the design requirement of a solid rocket motor, this paper discusses the flexible nozzle with ball joint, which includes the structural design of the flexible nozzle,3D modeling, kinematic simulation, modal analysis and static performance simulation.The structural design software CATIA V5is used to design the structure of the nozzle, and the main parameters are given in the paper. The Simdesigner module of CATIA is used to simulate and analyze the mechanism kinematics of the controlling mechanism after the3D modeling, assembly and correctly setting the kinematic pairs are done. The position, velocity and acceleration curves of the nozzle CM, which under the situation of the links in uniform movement, are given, so are the position, velocity and acceleration of the plunger of the connecting rods which under the situation of the links in uniform swing.Structure performance simulation of the flexible nozzle with ball joint is done by ANSYS Workbench. After the model simplification, setting contacts, applying constraints and loads and selecting appropriate material, the FE model of the nozzle is established. Then beginning the modal analysis and the first six modal shapes of the nozzle are obtained, and analyzing the statics performance of the nozzle, the deformation and stress under a certain pressure are obtained.The simulation results show that, under the drive of the control mechanism, the nozzle can swing in XY and XZ plane, but not axial endplay along X-axis. The first resonant frequency of the nozzle is65.46Hz, which far from the frequency of the hydraulic control mechanism and ammunition injection. The maximum stress within the nozzle is less than the allowable stress of the material selected. The designed structure of flexible nozzle on the performance of all aspects meets the design requirement.