Research On Adaptive Pressure Relief Control Of Fixed-geometry Hypersonic Inlet Working At Large Mach Number Rang

The research for scramjet inlet attracts much attention as an important part of hypersonic vehicle,which influences the thrust force directly. A concept of adaptive pressure relief control was proposedfor the contradiction between total performance at high and low Mach number and self-startingperformance at low mach number.First, the pneumatic principle of the adaptive pressure relief control was studied. And then thelaw about the location, direction, effective area and the number of adapted pressure relief slot wasstudied with the outgassing rate and performance of two-dimensional hypersonic inlet, whichself-started at Mach=3.8with one slot at shock wave reflect point of Mach=4and the other threeuniform distribution upstream, which outgassing rate was less than2%. The optimization of the areaof the slot was studied to decrease the outgassing rate, and at the same time improve the performanceof the inlet.Based on the result of numerical simulation, A hypersonic inlet with the concept of adaptivepressure relief control was used for the wind tunnel test. The result shows that: the inlet couldself-start at Ma=4; and the inlet had a better total performance, and the back-pressure capability hadgreat improvement. the result of numerical simulation was credible as it had a good anastomosis withwind tunnel test.Finally, the relationship between the adaptive pressure relief control and inlet design wasresearched, especially, the interior contraction ratio. The result shows that: it can reduce the number oreffective area of the slot to less the outgassing rate when the inlet has a lower interior contraction ratio,but when it got bigger, the inlet would need4slots. And there is a formula to measure thecompensation quantity for the area of throat by the adaptive pressure relief control which turned tostarting region under Kantrowize criterion.