双支板超燃燃烧室燃烧状态的试验研究

Experimental Investigation on Combustion State in a Dual-Strut Supersonic Combustor

关键词:  超燃冲压发动机  燃烧状态  当量比分配  动态喷注  分级喷注  

Key words:  Scramjet engine  Combustion state  Equivalence ratio distribution  Dynamic injection  Staged injection

摘要:

通过直连试验，对双支板超燃燃烧室进行了煤油分级喷注研究。在试验中发现，这种燃烧室在来流及供油条件完全相同的条件下，出现了两种稳定的燃烧状态:如果上游支板喷注的燃料在当地燃烧，那么称之为上游燃烧状态；如果上游支板喷注的燃料没有在当地燃烧而是与下游喷注的燃料一起在下游燃烧，那么称之为下游燃烧状态。针对这一现象，本文从当量比分配的角度，对这一现象进行了试验研究。在总当量比为1.0时，经过对试验结果的分析，选取了一个特定位置，称为特征点。通过动态试验获得了特征点的压力，建立了它和上游支板喷注的当量比之间的关系，并利用这一关系描述了两种燃烧状态出现的当量比条件。一维冲量分析法的结果表明，上游燃烧状态的燃烧室内推力比下游燃烧状态高73N。

Abstract:

Staged injection in dual-strut supersonic combustor fueled by liquid kerosene was experimentally tested in directly-connected facility. Two kinds of steady combustion state were found in the identical incoming airflow condition and injection condition. If the fuel injected from upstream strut combusted locally then it was named as upstream-combustion state，and if the fuel injected from upstream strut combusted downstream then it was named as downstream-combustion state. This phenomenon was investigated from equivalence ratio distribution. In the condition of the total equivalence ratio being 1.0，a feature point was chosen by analyzing the results. The relationship between the pressure of the feature point and the equivalence ratio of the upstream was obtained through the dynamic injection experiments，and the conditions in which the two combustion states happened were described through this relationship. The results of one-dimensional impulse analysis method show that the thrust in upstream-combustion state was 73N higher than that in downstream-combustion state.