Acoustic characteristics tests by a simple test models for simulating the internal shape of rocket motor

Abstract

Combustion oscillation is a combustion instability in solid propellant rocket motor and that occurs when the pressure oscillation is amplified by the resonance frequency of rocket motor internal shape. In this study, the acoustic analyses were conducted in the internal shape of rocket motors. The results of analysis show that the modal damping ratio of star-forward shaped grain is larger than the star-aft shaped grain and qualitatively correspond with the combustion test results. Prior to the acoustic analysis, the conditions for acoustic analysis were studied by a simple test models for simulating the internal shape of rocket motor.