Test Study On Atomization Of Secondary Liquid Flow Of Fluidic Nozzle Throat

Fluidic nozzle throat scheme is in the vicinity of the throat of the engine through secondary fluid jet,interaction so as to change the mainstream throat shape and distribution area of the secondary flow and the mainstream;meanwhile the fluid nozzle throat and secondary flow vector control system can be combined with each other,this technique can at the same time achieve the regulation of the size and the direction of the thrust of solid rocket engine.Relative to the secondary flow for the gas,when the secondary flow is liquid,it can more easily realize the flow of the secondary flow regulation and multiple starts,and secondary flow volume of storage system can be smaller,thus gas-fluidic nozzle throat scheme has a greater application value in engineering.Also,if the injection liquid flow is oxidizing liquid,secondary flow and mainstream mutual effection can conduct secondary combustion and release much heat,and enhance the ability to control fluidic nozzle throat.Atomization effect of secondary flow interaction with mainstream is better,the secondary combustion the throat is more fully,the ability to control fluidic nozzle throat is higher.Therefore,it is necessary to test and study the effect of the throat atomization when secondary flow is the liquid.Study on atomization effect of secondary flow interaction with mainstream,to provide a reference for thermal test experiments using gas-fluidic nozzle throat engine design,and the study helps to deepen understanding of the mechanism of the secondary flow.The main research content of this paper is to study the atomization characteris-tics of secondary flow interaction with mainstream and the flow characteristics in the fluidic nozzle throat of solid rocket motor.In order to study atomization effects of injector in the cross-flow and the flow characteristics,this study intends to use mature Malvern particle size analyzer and high resolution high speed camera,a series of cold-flow tests were performed using impinging injector,reverse injector and horizontal injector.The droplet diameter of spray field at the exit of engine nozzle and spray distribution index were studied at different test cases.The particle size data and flow characteristics can be obtained by experiments at different pressure ratios,flow ratios and injection schemes.The research results will provide an important basis for the subsequent engineering applications and engine design.