Study Of Aerodynamics And Drag Reduce For The Base Bleed Projectile

The long range projectiles and weapons play a more and more important role in modern war. Range enlarge technologies are become the important goal of modern projectiles development. Base bleed technology with highly range enlarged is extensively used. A method of drag reduces for base bleed projectile is studied in this article.The grids of the whole flow field of projectile are generated by the algebraic method. The MacCormack scheme is applied to solve the three dimensional Euler equations for the parameters of the entire flow field around the projectile with and without base bleed. The coefficients of aerodynamics are calculated by the flow field parameters. The results accord with the aerodynamic theory.The base bleed mess rate I is always used to deal with the base bleed boundary condition. It comes from the mess accretion consideration. A new method to treat the base bleed boundary condition is used in this article. This method puts the focus on the energy which depends on the temperature of the base bleed gas. The results show that energy is effective and the key point of drag reduce for base bleed projectiles. It can be referenced for the further improvements of the base bleed projectiles.