NUMERICAL INVESTIGATIONS TO ESTABLISH CORRELATION BETWEEN BALLISTIC PROPERTIES EVALUATED FROM VARIOUS SAB-SCALE MOTORS

Evaluation of ballistic properties of solid rocket propellant is most critical activity for determining the performance of missiles or space vehicle. Among various available technique for evaluation of these properties, subscale motors are most accurate and reliable. Progressive and neutral sub scale motors (SSM) are mostly used for estimation of these properties. The paper proposes a methodology using numerical simulations for quantifying the impact of hump effect, tail off effect, dimension tolerances and instrumentation errors on the properties calculated from both the SSM. Simulated pressure time profile is numerically generated by varying burn rate, pressure index, throat diameter and grain geometry using an experimentally validated model. Effect of above mentioned parameters are incorporated in simulated profile using models reported in literature. A systematic analysis of these simulated data is conducted and limitations of progressive SSMs is established. The study brought the robustness of neutral BEMs for computation of ballistic properties.