Numerical Investigation of Aerodynamic Characteristics of a Missile with "×" Type Layout

The aerodynamic characteristics of a certain type of missile with "×" layout were analyzed with Computational Fluid Dynamics (CFD) methods. A three-dimensional model of the missile and external flow field was established, and mixed hexahedral and tetrahedral grides were generated in the computational domain. The flow mathematical model was established with the Renolds averaged Navier-Stokes (RANS) equations and Spalart-Allmaras (SA) turbulence model, and the finite volume method was used for the solution. The aerodynamic characteristic parameters of the missile at different Mach numbers and angles of attack (AOA) were obtained and analyzed. The simulation results show that as the AOA increases, the drag coefficient exhibits a non-linear growth pattern; as the Mach number increases, the drag coefficient first increases and then decreases. Within the studied AOA range, the variation of lift coefficient with AOA under different Mach numbers maintain high linearity and no stall occurs. With the increase of Mach number, the lift-drag ratio decreases in subsonic and transonic conditions, and does not change significantly in supersonic conditions. The slope of the AOA-pitch moment coefficient curve is negative, indicating that the missile is statically stable; and within the studied AOA range, the variation of pitch moment coefficient with AOA maintains high linearity under different Mach numbers. The research results have significant reference value for the aerodynamic design, ballistic calculation, and control system design of missiles.