Experimental and Numerical Analysis of Supersonic Mortar Projectiles

Abstract

The aim of “Crawfish – Ammunition†project is to develop supersonic mortar projectile for “Crawfish†(“RAKâ€) self-propelled mortar. This projectile has been developing in Military Institute of Armament Technology. As a main goal of HE projectile is to achieve range above 10000 m, that implicate muzzle velocity according to 500 m/s. Nowadays literature about this kind of projectiles is very poor. In the article authors showed results of exterior ballistic analysis for several types of supersonic mortar projectiles. Analysis was made according to experimental data and numerical calculations. Experimental data was collected on maximum range shooting tests at 500 m/s velocity with 45 degrees elevation. In flight projectile was observed by radar to measure their position and velocity and to gain the data enabled to calculate drag laws for different shape supersonic mortar projectile and quality of projectile stability. Second part of article consists of the CFD numerical analysis of these projectiles. Using Ansys Fluent program authors calculated drag coefficients of these projectiles. Authors estimated the accuracy of CFD method comparing numerical and experimental data. After that they checked drag coefficients of different parts of projectiles (primer, ogive, fins etc.). Analysis of radar data showed drag fluctuations at low velocities of flight (0.5 – 0.8 Ma). CFD method was used to calculate center of force and stability moments. Drag coefficients at different yaw angles was also estimated. That data was used to model yaw of projectiles to compare with experimental data. Finally authors formulated conclusion about accuracy and possibilities of using CFD methods in exterior ballistic.