燃气发生器低频非稳态燃烧统计分析

针对冲压发动机地面试验需求，设计燃气发生器，通过试验统计研究其燃烧稳定性特征。结果表明：该燃气发生器发生低频非稳态燃烧的概率为32.7%，存在两种振荡形态。一种存在振荡主频，即低频不稳定燃烧；另一种没有主频，燃烧形态为粗暴燃烧。粗暴燃烧发生概率高且与余氧系数存在较强的相关性，低频不稳定燃烧发生概率低。两种形态的振荡能量分布位置不同。
In order to satisfy the demand of scramjet ground test, a gas generator was designed. Tests were taken to study the stability characteristics of combustion using the statistical approach. Results indicate that the proportion of unsteady combustion accounts for 32.7%. All unsteady combustion occurred belongs to low frequency oscillation. There are two kinds of oscillation forms. One has dominant frequency crest, which has low frequency combustion instability or chuffing. For the other one, there is no dominant frequency crest，namely rough combustion. The probability that rough combustion occurs is relatively high and it is related to the excess oxidizer coefficient, while the low frequency combustion instability occurs with lower probability. Result shows that the energy distribution of the two unsteady combustions is different. 