Study And Numerical Simulation Of Combustion Characteristics Of Base Bleed Projectile

Theoretical studies and numerical simulation of the combustion characteristics of the base bleed projectile are conducted. The characteristics of the internal flow field and the key factors of the drag reduction for the base bleed projectile have been obtained by establishing a general interior ballistic model of the base bleed projectile.The combustion in the gun bore of the base bleed charge is considered in one-dimensional combustion model of the base bleed device. By coupling the base bleed cavity equations and the gun interior ballistic equations, one-dimensional distributions of the pressure, temperature and velocity in the base bleed device and gun bore have been analyzed.Based on analysis of combustion models of base bleed charge available in and abroad, there advance an improved model to describe the combustion process of base bleed charge, where the fill effect of combustion-gas is considered. On the other hand, the applicability of the burning rate formula under dynamic state in upper air is also considered.The supersonic flow field over projectiles including base flow is studied in detail by the commercial software FLUENT. The two-dimensional axially symmetric flow field with base bleed under different Mach number is calculated. The affect of the Mach number and the base bleed to the flow field is analyzed, which will have some values in studying the mechanism and effect for the drag reduction of the base bleed device.