氢/空气超音速燃烧自燃规律的实验研究

对平行喷射氢／空气超音速燃烧自燃规律进行了实验研究。主流空气用氢和空气燃烧补氧的方式加热到温度1000～2100K，压力0．8～1．6MPa。发现滞止温度、滞止压力和燃烧室内部构型等都对自燃有影响，特别是滞止温度和内壁构型的影响非常大。研究了四种试验段构型的自燃规律，找到了它们的自燃极限条件。对于光滑内壁构型，当温度接近自燃极限时，发现了有兴趣的现象并作了讨论。

EXPERIMENTAL STUDIES OF AUTOIGNITION OF HYDROGEN JET INJECTED PARALLEL IN A SUPERSONIC AIR STREAM

Autoignition tests of a model scramjet combustor were conducted using parallel sonic injection of gaseous hydrogen from the base of the strut into supersonic air stream. The vitiated air was produced by burning of H2, O2 and air up to 1000~2100K at stagnation pressure ranging from.0. 8 ~ 1. 6MPa. The experimental results show that autoignition was sensitive to a number of parameters: air stagnation temperature and pressure, and wall configuration of the combustor, The temperature and wall configuration has significant effect on the autoignition. Four different wall configurations were tested and their autoignition limits were given. It was found that autoignition would occur downstream of the duct exit then ignite the whole combustor through boundary layer or burning only outside of the duct for smooth wall when temperature was close to the autoignition limit.