Investigations Of Supersonic Mixing Enhancement Technology And Drag Of Strut

The supersonic mixing enhancement technology based on strut was studied in present thesis. Especially, the mixing process of fuel ejected by strut and the drag of strut were studied comprehensively.The flow field of strut with different structure parameters was studied by experimentation and calculation in non-reaction flow. It is founded that the strut flow can be affected by sweepback angle greatly. The interaction between the bow shock caused by the leading edge of swept strut and the boundary layer makes the boundary layer separate at large degree. The shock of the leading edge of unswept strut is less intensive. The alternating-wedge structures of strut produce intense vortices, which make the shear layer after the strut develop more quickly.The strut flow with gas/liquid jet and the mixing performance of strut with liquid jet were studied by experimentation and calculation in non-reaction flow. The results of investigation show that the flux of gas jet is too small to affect the strut flow under the test condition. The liquid jet has great influence on strut flow, which make the expansion wave and shock wave behind the strut disappear. The alternating-wedge strut produce more intense spanwise vortices than other struts do, which make the diffuseness of fuel in mainstream more quickly, and enhance the mixing.Experiments on the drag of strut were conducted with force measurement system. The investigations on the drag of strut under non-reaction condition and combustion condition, with different strut structure parameter and fuel equivalence ratio, indicate that drag of strut of cold flow increases with height increase, decreases with sweepback angle increase. The strut drag becomes smaller under combustion condition than in cold flow, and decreases with fuel equivalence ratio increase.