Flow simulation and drag anatomy for antitank projectile configurations

Abstract

Introduction S projectile configurations (Fig. 1) are fired against armored targets so that the spike acts as a stand-off distance between the armor and the shaped-charge warhead. The conenosed configurations, also shown in Fig. 1, may provide a windshield for reducing the drag, and provide a standoff distance as well. The lower drag for this cone-nosed class should extend the range for these projectiles, if launched at the same speed. In prior studies,' computational results for spiked configurations with increasing geometrical complexity were presented. In Ref. 1, configurations of spikes with no vortex rings and bodies with no base-flow simulations were considered. In Ref. 2, the vortex generator ring was added and the body base flow was computed. The present work adds another degree of complexity, represented by an aftbody with steep boattail and tail fin boom. It thereby lays the foundation for the final step, which is the inclusion of fins on the tail boom. The computations were made using the axisymmetric flow simulation code, using the zonal overlapping topology of Ref. 3. It uses the explicit, time-dependent McCormack numerical scheme. The purpose of this work is to provide the drag anatomy of each geometrical component of the projectile body, for both the spikeand the cone-nosed projectiles, at high supersonic speeds and zero angle of attack.