Preliminary Design Method for Base Bleed Unit

Abstract

Base bleed is a system for base drag reduction of projectile by gas injection into base area. The gas injecting through orifice is generated by combustion of solid propellant grain. Base bleed output mass flow rate depends on the chamber pressure, the pressure into which jet exhausts, time and spin rate. An analytical interior ballistics model of base bleed developing in the paper is based on basic fluid dynamics and experimental results of measured time for base bleed burning in the field of radial acceleration. By iterative method, chamber pressure and mass flow rate can be estimated during the base bleed work. The model is verified by available experimental results.