Burn Rate Evaluation with a New Design of Ballistic Evaluation Motor

Abstract

In this work burn rate evaluation was carried out with a new design of sub-scale motor having 3kg propellant mass. The 3kg BEM when compared to the 40 kg sub-scale motor, commonly used in India, has several advantages. It poses less processing hazard and is also more suitable for conducting costly experimental formulations. The port configuration of the 3kg BEM was kept same as its 40 kg predecessor. The Klemmung, at all corresponding web thicknesses, could therefore be kept same. The L/D ratio of the 3kg BEM was reduced to 3 from a L/D ratio of 5 for the 40kg BEM. A new igniter was designed for the 3kg BEM and a reduction in ignition delay from 40ms to 24.5 ms could be achieved. The burn-rate obtained from the 3kg BEM varies w.r.t. the 40 kg BEM in the range (-)1.28% to (+)1.99%.