Numerical Simulation Calculation and Analysis of the Effect of Rocket and Duck Rudder on Its Aerodynamic Characteristics and Flexible Deformation

Abstract

Based on inertia relief and CFD/CSD two-way coupling methods, the static aeroelasticity numerical simulation of a simply guided rocket with duck rudder actuator has been done, and the influence of duck rudder on aerodynamic characteristics and flexible deformation has been analyzed. Firstly, the lift, drag force and pitch moment coefficients, etc. had been calculated by using CFD method based on SST k-ω turbulence model, the error was less than 10 percent compared with the experimential data, and it verified the accuracy of fluid domain numerical method. Then, the two-way fluid-structure interaction simulation on the rocket and the contrastive analysis were done based on ANSYS Workbench multi-physics coupling simulation platform. The results show that duck rudder has a larger influence on rocket aerodynamic characteristics, by analysing the rocket aerodynamic coefficients under the conditions of without duck rudder, 0° rudder angle and 10° rudder angle, and it shows that the lift force and pitch moment coefficients change 5 to 30 percent with or without duck rudder and angle. Considering the influence of flexible deformation on aerodynamic coefficients, the flexible deformation has a more influence on the lift force and pitch moment coefficients, it reflects that the flexible deformation leads to the lift force coefficients smaller and pitch moment coefficients absolute value smaller, the maximum influence can reach to 5 to 10 percent. Meanwhile, the results show that the maximum deformation of rocket occurred in the middle of the rocket body, and the maximum equivalent stress occurred in the empennage of the rocket. Therefore, in the design of simply guided rockets, it’s very important to consider the influence of duck rudder on the aerodynamic characteristics and flexible deformation.