Predictions of Coupled Motion Dynamic Derivatives of Projectile

For investigating the aerodynamic characteristics of a novel hedgehopping projectile under the angular motion coupling of pitching and rolling, a method to deal with simulation of the complex angular motion is proposed based on the Euler rotation theorem and sliding meshing technique. By applying this method, and solving and identifying the unsteady aerodynamic parameters, the influences of the projectile’s rolling motion on dynamic derivatives of pitching combination and lift coefficient under various Mach numbers are explored. The results indicate that: in the solving process for the unsteady flow field, the proposed method can eliminate the accumulative errors in calculation of attitude angles effectively, realizing the accurate simulation under arbitrary given angular motion; due to coupling with the pitching motion, the projectile’s rolling motion can generate significant influences on the identification results of dynamic derivatives of pitching combination and lift coefficient, and in details, the identification results always decrease along the increasing the rolling frequency under conditions of different angles of attack.