Experimental Research On Performance Of Pulse Detonation Rocket Engine

Pulse detonation rocket engine (PDRE) is a new concept of propulsive device which takes fuel and oxidizer, utilizes high temperature and pressure gas produced by pulsed detonation wave to generate thrust. PDRE has great potential to become one of important propulsive devices of spacecraft in 21^st century because PDRE has many desirable advantages, including high thermodynamics cycle efficiency, simple configuration and high specific impulse.In this paper, the operation principle and working cycle of two-phase PDRE are analyzed firstly. The experimental system of PDRE is built up. It consists of fuel/oxygen supply system, ignition system, thrust testing stand system, engine parameter data acquisition and processing system. The multi-cycle PDRE model of 120N thrust was designed. Then on the tube of inner diameter 50mm, length 1.2m(model I) or the tube of inner diameter 62mm, length 1.1m(model II), many experiments are performed using kerosene as fuel and oxygen as oxidizer. Firstly, the effect of thrust and specific impulse was performed on different head constructions, different volume of detonation tube, different equivalence ratio. With different volume tubes, the tube of small volume can get the higher thrust/volume. The experimental results indicated that the thrust and the specific impulse increase with the increase of the equivalence ratio under different equivalence ratio ranging from 0.5 to 1.7. It means that the increase of the equivalence ratio can increase the performance of PDRE. Then 10 nozzles from 3 typical types are chosen under experimental tests. The results show that all nozzles can augment the thrust of baseline PDE and there is an optimal nozzle area ratio where thrust augmentation is maximized. Amongst all tested nozzles, the maximal augmentation of 24% is attained by a convergent-divergent nozzle. Moreover, it is validated that fill-fraction has little effect on thrust augmentation. Finally, the experiment of high frequency was performed based on the research of solenoid valve. The highest frequency reached 25Hz.