Principle Experimental Research On Variable Thrust Pintle Motor

Controllable thrust propulsion technology will be a solution to the propulsion requirements for the next generation of missiles. Pintle controlled solid propulsion is one approach to achieving this goal. Using pintle technology, a conventional solid propellant rocket motor can provide variable thrust levels, increasing the energy utilizing efficiency and improving the capability of the missile. In this article the experimental pintle motor was designed and the principle experiments were carried out. The charachteristics of pintle motor was also analysed. Through the experiments and theoretic anlysis, the principle of pintle motor was opened out, the law of main factor were analysed. The main contents and results are included as following:The main influence factors on thrust adjusting character of pintle motor were sumarized. The influence of burning rate exponent and throat diameter on thrust was analysed and the relationship between pressure and thrust ratio of pintle motor was obtained.The internal ballistics prediction method of pintle motor was developed and internal ballistics of test motors were calculated. The experiments show that this prediction mothed is valid in certain degree.The experimental system of non-coaxial pintle motor was established including pintle motor, driving system, measurement and control system. In this system the problems of pintle configuration, dynamic seal, driven equipment and thrust measurement equipment were well solved. The breaking of pintle in experiment was finally solved by changing the material and improving the pintle configuration. The main reason of slowly climbing of pressure was found out by analyzing and some validating experiments. A pintle motor test with high combustion temperature propellant was carried also. A coaxial pintle motor was designed and some preliminary tests were carried out. These experimental results can provid referrence for pintle motor study.