Research On Working Characteristics Of Multi-pulse Pasty Propellant Rocket Engine

Pasty propellant rocket engine as chemical rocket propulsion is a new developing direction of technology,the advantages of solid,liquid rocket engine,because of its unique advantages,has broad application prospects in the field of aerospace,attracted industry wide attention.In this paper,the working characteristics of multi-pulse pasty propellant rocket engine are studied as follows.(1)Based on Carreau constitutive model of pasty propellant and commercial software,the flow process of pasty propellant flowing through multi-hole nozzles into combustion chamber under the extrusion of supply system was simulated.The flow characteristics of pasty propellant flowing through different multi-hole nozzles under the same extrusion pressure were analyzed.The simulation results show that the outlet velocity of pasty propellant increases exponentially with the increase of pressure difference when the pressure difference between the two ends of the flow field is low,while the outlet velocity of pasty propellant increases linearly with the increase of pressure difference when the pressure difference is high,and there is a transitional stage between the two stages.For the flow situation of multi-hole nozzle,pasty propellant in the transition stage occurs in a very short range of pressure difference,and the more dense the distribution of through holes and the larger the diameter of the holes,the smaller the pressure difference required for the occurrence of the flow rate jump phenomenon.(2)A multi-pulse pasty propellant rocket engine ignition test system was designed and built.Based on the theory of continuous reaction,an anti-tempering device is designed.Under the action of pulse control system,the pulse working time and pulse interval of multi-pulse pasty propellant rocket engine can be adjusted.The general layout of ignition test system and the functions and characteristics of each subsystem are introduced in detail,and the key components and parameters are calculated.The pasty propellant supply test and multi-pulse simulation test were carried out by using the designed ignition test system.During the test,the components of the system worked normally,and all the performances of the system met the requirements of operation,and the further ignition test could be carried out.(3)The interior ballistic characteristics of multi-pulse pasty propellant rocket engine were simulated and ignition tests were carried out.The results of combustion chamber transient pressure test show that the ignition pressure build-up process of pasty propellant rocket engine is quite different at different mass flow rates.In view of the phenomenon that the ignition process of paste rocket engine shortens with the increase of mass flow rate,the elastic effect of pasty propellant is proposed and verified as the main factor affecting the ignition performance of the engine.Multi-pulse ignition test was carried out.The results show that the higher the mass flow rate,the better the performance of pasty propellant rocket engine.