Publication de 6 numéros par an
ISSN Imprimer: 2150-766X
ISSN En ligne: 2150-7678
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Computer Codes for Ballistic Performance Calculations of Base Bleed Propellant Grain
RÉSUMÉ
Concerning shell external ballistics, different technical solutions are studied in order to improve aerodynamic performance of a shell. The solution named base bleed consists of injecting a hot gas at a low velocity into the depressional flow area. Preliminary design of a base bleed propellant grain has to satisfy requirements generally expressed as a shell range increase against available grain volume. In order to adapt the propellant grain ballistic performance to the shell trajectory conditions, two different investigations have been developed. The first investigation is essentially theoretical and consists of computer simulations of the flowfield near the shell base with and without effect of subsonic injection. The second investigation is more empirical and consists of analysing the shell velocity evolution by means of radar measurements in order to determine drag reduction factor due to the base bleed effect. The organization of the developed ballistic computer codes and some results are described in this paper. The results of the two studies give ballistic data necessary for simulations of base bleed shell trajectories.