NUMERICAL MODELING AND EXPERIMENTAL VERIFICATION OF A NOVEL BASE BLEED DESIGN

摘要

Understanding the behaviour of base bleed propellants in the bore of a gun is a rapidly developing field. The XM982 Excalibur projectile currently under development for the U.S. Army and the Kingdom of Sweden will contain a novel base bleed design. The design has been challenging due to the stringent weight requirements of the system. BAE Systems Bofors AB and the U.S. Army Armament, Research, Development and Engineering Center (ARDEC) have been collaborating to develop and analyze this novel base bleed device which was designed by BAE Systems Bofors AB. The Analysis and Evaluation Technology Division at ARDEC and BAE Systems Bofors AB collaborated in the design of a specialized 155mm XM1073 Instrumented Ballistic Test Projectile (IBTP) [1 ] as an experimental vehicle to determine pressure differential between the interior of a base bleed cavity and the bore of the weapon. The projectile was instrumented with pressure transducers and with the data telemetered to a ground station. The pressure differential was tracked to assure base structural integrity both within the tube and immediately after gun launch. The numerical modeling has been carried out at BAE Systems Bofors AB using the Matlab software. The data was taken from this model and used in finite element and CFD code run at both BAE Systems Bofors AB and ARDEC to assure adequate design margin exists in the base. The match of the experimental data to the model results was excellent.