Simulation Study On Aerodynamic Characteristics Of Small Bombs With Three - Wing Aerodynamic Layout

Miniaturization is a tendency of guided bomb. Guided bomb owns the characteristics of small diameter, lighter weight, and most of them do not carry power plant. To improve firing range, high aspect ratio aerodynamic shape is often used, but aerodynamic distortion occurs when the wing is flying. This thesis mainly focus on structure factors of projectile, wing type and wing shape etc. Design a small three-wing aerodynamic configuration of guided bomb, and simulating its aerodynamic characteristics and aerodynamic deformation, providing a reference for designing and developing the small-size guided bomb.Use "Spalart-Allmaras" turbulence mode, simulating the aerodynamic characteristics of bomb under the subsonic speed, getting the rule of how wing shape influence the aerodynamic characteristic of three-wing aerodynamic configuration bomb and the rule of how wing numbers influence the aerodynamic characteristic of bomb when the wing shape is same.Aiming at the problem of wing deformation when bomb in flight. Using bi-directional fluid-structure interaction, simulating and calculating the aerodynamic deformation of elastic-wing of three-wing configuration bomb. Getting the rule of how wing material influence the aerodynamic deformation and the rule of how wing deformation influence aerodynamic parameters, and compared to aerodynamic performance of rigid wing.Results showed that:(1) For one-half wing exhibition respectively is 100mm,150mm, 200mm,250mm of three wings bomb, the higher one-half wing exhibition, the bigger its lift-drag ratio and better stability; (2) For bomb that the front angle respectively is 30°,41°, 60°,90°,120°, the more small of front angle the better stability, In the situation of small attack angle, the lift-drag ratio is maximum when bomb of front angle is 60°; (3) For bombs with same wing shape but the wing numbers respectively is two, three, four, the lift-drag ratio of two-wing bomb is maximum, and these three ways of bomb have an almost closed stability; (4) For three wings of bomb in four wing situations, the aerodynamic characteristics of elastic wing is better than rigid wing, and in same range, the modulus of wing tablets is more small, the aerodynamic characteristics of bomb is more better.