超燃冲压发动机直连式试验非均匀吹除装置研究

Non-Uniform Blowing Device for Scramjet Direct-Connect Test

关键词:  超燃冲压发动机  隔离段  吹除装置  非均匀来流  吹除参数  直连式试验

Key words:  Scramjet  Isolator  Blowing device  Non-uniform flow  Blowing parameters  Direct-connect test

摘要:

为了能在直连式试验平台上获得矩形截面超燃冲压发动机的真实隔离段入口来流，在风洞喷管和隔离段之间添加吹除装置，装置的上下壁面开缝并向缝中注入空气，使均匀来流变成非均匀来流。以模拟飞行马赫数6.0条件的隔离段入口流场为目标，使用商用软件Fluent对吹除装置进行数值模拟。研究吹除缝的位置、缝的宽度及吹除装置长度对吹除结果的影响，并确定合适的吹除装置几何尺寸。结果表明，该吹除装置能够模拟隔离段入口的非均匀来流，吹除装置出口截面的质量平均马赫数与自由射流条件下的偏差不超过0.02（约0.8%），总压偏差不超过0.03MPa（约2.1%）。

Abstract:

A non-uniform blowing device was added between the direct-connect facility nozzle and scramjet isolator to simulate the real flight flow conditions. The cross section of scramjet isolator is rectangular. The blowing device is an additional isolator with slits. The slits are distributed on the upper and lower wall surfaces of the device， and air is blown into flowfield from these slits to make the uniform experimental flow transforming to non-uniform. Numerical simulation about blowing parameters were conducted using commercial software Fluent. The flow paramaters at isolator entry simulates those of flight Ma 6.0. Geometry parameters of blowing device include slit location， slit width and blowing device length. These geometry parameters are compared to design the optimized blowing device. The results show that this blowing device could simulate the non-uniform flow of isolator， the deviation of mass-weighted average Mach number between the blowing condition and free-jet test is within 0.02 （about 0.8%）， deviation of total pressure is within 0.03MPa （about 2.1%）.