Analysis on response of pressure in non-coaxial variable thrust pintle motor

In order to analyze the performance of variable thrust pintle solid rocket motors, an experimental system of non-coaxial pintle solid rocket motor was designed, and through this system, experiments that validate variable thrust principle were carried out. The pressure curve of the principle experiment shows that the change of pressure was accomplished perfectly during the experiment and the transition from low pressure to high pressure was realized. Afterwards, further experimental researches were done so as to find the motor free volume, pintle movement state, equivalent throat structure, and the influence of propellant composition on the response of pressure during the change of thrust and whether the pintle can be positioned with single action or not. The results show that the response time of propellant is the primary factor which effects the response of pressure. The experiment concerning dual pressure peak was carried out using the proven low pressure exponent propellant. The results show that the rate of the pressure drop is much faster than the rate of the pressure build-up. The conclusion may provides a reference for analysis on response of pressure in non-coaxial variable thrust pintle motor.