Experimental Study Of High Temperature Hydrocarbon Component Injection Characteristic

Re-Cooled Scramjet use endothermic hydrocarbon fuels to cool the engine wall, the fuel Pyrolysis to micro molecule hydrocarbon after absorb heat from the wall. In this paper, we research on the injection characteristics of ethane which is one of the pyrolysis-gas based on advanced optical measuring instrument PIV and computational fluid mechanics software Fluent.We design and build the gas injection experimental bench, design and produce nozzle,gas-protection chamber and tracer particle added-in chamber. Throughout the analysis of the original pictures captured by PIV and data extraction, research the influence of temperature,pressure, and size of nozzle on axial velocity and taper angle. The experiment can only show some of the injection characteristics of the ethane, so we use simulation of fluent to add the experiment. The simulation mainly observe the formation and development of shear layer,cloud atlas of temperature, pressure and turbulence energy and their corresponding scalloping curve, the influence of pressure, temperature on potential core longitude and penetrating length.It can be discovered form experiment that: In the flow field distribution and velocity distribution of the axial: The viscous interaction between ethylene and air makes the air entrained into injection fluid, make the whole injection flux grow in axial direction, lower the injection velocity. Ethylene concentration is getting lower in the axial and radial direction along with the development of injection flow, gas injection has diffusivity and similarity. The influence of different conditions of pressure, temperature on spray axial speed and cone angle:With pressure getting higher, axial velocity gets higher, decreasing tendency of axial velocity under different pressure is the same. The influence of temperature on velocity mainly reflects on the nearby of nozzle. Cone angle i decreases with the temperature increasing and pressure increasing. The numerical simulation results showed that: The penetrating length increase with the pressure increasing and decrease with the temperature increasing. The potential core longitude of injection can only be influenced by pressure and increases with pressure increasing while temperature has nearly no effect. At last, the research content is concluded properly and the future works are prospected.