Aerodynamic optimal design of guided bullets based on improved orthogonal test

With the development and miniaturization of guidance technology, guided bullets have revolutionaryly improved the accuracy and survivability of sniper. Different from the designing of traditional bullets that focus on minimizing drag, the guidance raises the requirement of high lift-drag ratio of guided bullets during maneuvering to ensure the efficiency of maneuver and the ability of storing energy. In this paper, based on the improved orthogonal test optimization, the boundary between each segment of the projectile is selected as the control factors, and lift-drag ratio under the maximum rudder deflection is set as the objective factor to optimize aerodynamic shape of the guided bullet. In terms of conclusion, the maximum lift-drag ratio is increased by about 80%, which shows that the optimization has significant effect. The proposed new method improves the searching ability while taking the processing capacity of the control factors and computational cost of orthogonal test into account. It has certain significance for the solution of low-dimensional unconstrained optimization problems and provides a reference for the design of guided bullets.