Numerical Simulation And Experimentation Research On Vortex Enhancing Combustion Of Solid Fuel Ramjet

Solid fuel ramjet (SFRJ) has wide application future on supersonic tactics missiles and increasing range projectiles because of its simple configuration, great specific impulse and excellent safety performance. However, the disadvantages of SFRJ such as low regression rate and bad combustion efficiency have extremely restricted its engineering application on missiles. Vortex enhancing combustion is a new technology to resolve some combustion problems of SFRJ. But the research on this technology is just in the initial stages of grope and it's far away from engineering application. So the purpose of this paper is to analyze qualitatively the influence of vortex flow on inner flow and combustion progress, meanwhile it is mainly to explore some measures of eliminating the disadvantageous impact of vortex in order to establish a foundation for the application of SFRJ on weapon system.In the paper, the combustion and flow within solid fuel ramjet is analyzed and the numerical simulation model of three-dimension, turbulent flow, multi-substances and chemistry reaction is established. By numerical simulation method, it synthetically evaluates the influence of vortex on performance of SFRJ based on inner flow and solid fuel combustion analysis of SFRJ in the circumstances of vortex. The results show that: Firstly, vortex flow can enhance the mixing of central airflow oxygen-riched and fuel-riched gas near solid fuel and destroy the recirculation zone at the same time, so the vortex will harm the flame stability. Secondly, when swirl intensity is small, the regression rate of solid fuel and the thrust of SFRJ increase rapidly, but when swirl intensity is too large, all parameters of its performance would decrease. Thirdly, flame stability improves notably and the axial distribution of regression rate of solid fuel becomes smoother when two coaxial flows is introduced into combustor. Finally, the technology of introducing anti-vortex flow into aft-mixing chamber decreases the loss of axial thrust at a certain extent, yet it also increases the loss of total pressure in aft-mixing chamber.Based on the design of SFRJ with swirler and the corresponding test system, separate igniter test and ignition test of SFRJ are carried out. The experimental results show that: Firstly, the peak value of ignition pressure and ignition time will rise linearly with the increasing of fuel of igniter. Secondly solid fuel burns unsteadily and both regression rate and performance of SFRJ decrease because of unsteady supply of air flux as well as too big throat diameter.This research is innovative which would contribute to the engineering application of SFRJ.