Dynamics Characterization of Missiles with Control Flaps Based on CFD

Numerical studies were carried out on the dynamics of the Basic Finner missile under supersonic velocity based on the three-dimensional unsteady N-S equation. Second-order upwind NND scheme finite volume was used to discretize the spatial derivative term of the flow-controlled equation group. The LU-SGS containing dual time steps was used to obtain higher efficiency and precision of time solution. A numerical model representing the relationship between the unsteady aerodynamic force/moment coefficients and state variables under single DOF (degree of freedom) pitching and rolling movements was built from the Etkin unsteady aerodynamic model. The numerical algorithm for solving damping-in-pitch derivatives and damping-in-roll derivatives by forced-harmonic analysis was proposed. The M910 target practice, discarding sabot with tracer (TPDS-T) was used as a validation example and proved that the numerical calculation gives the same result as the experiment. By simulating the forced pitching and rolling vibration of Basic Finner, the numerical identification succeeded in obtaining the damping-in-pitch derivative and damping-in-roll derivative to a higher precision than the calculated result obtained by the quasi-steady Euler equation. Besides, to address the longitudinal and horizontal cross coupling induced by the pitching movement, numerical identification was also carried out on the cross coupling derivative of Basic Finner when under forced pitching vibration.

The Research and Application on Computational Methods in Fluid Dynamics

The NND scheme based on Van Leer flux vector splitting is presented. The flow field of shock wave tube is calculated by the difference method presented in this paper, which shows that the presented finite difference method has fine calculation precision and efficiency, and could capture shock automatically.