燃烧室轴向和周向长度对气液两相旋转爆轰特性的影响

为了研究旋转爆轰发动机燃烧室轴向和周向长度对气液两相旋转爆轰特性的影响,采用守恒元和求解元(CE/SE)方法对带化学反应的汽油/富氧空气两相旋转爆轰理论模型进行求解,获得了气液两相旋转爆轰流场结构,并分析了燃烧室轴向和周向长度对燃烧室流场、爆轰波传播特性以及发动机推力性能的影响。计算结果表明:轴向长度对燃烧室上游流场影响甚小,却对下游流场参数影响较显著。随着轴向长度增加,燃烧室出口压力、温度、密度以及周向速度均降低,轴向速度则逐渐增大,同时发动机平均推力密度和燃料比冲先增大后减小。当周向长度过短,燃烧室内难以形成自持传播的爆轰波,随着周向长度增加,上游爆轰波强度增加,对应的流场参数均有所增大,但发动机推力性能略有所降低。

Influence of axial and circumferential lengths of combustion chamber on gas-liquid two-phase rotating detonation characteristics,

In order to study the influences of axial and circumferential lengths of rotating detonation engine combustion chamber on gas-liquid two-phase rotating detonation characteristics, the theoretical model of gasoline/oxygen-enriched air two-phase rotating detonation with chemical reaction was solved by conservative element and solution element (CE/SE) method. The flow field structure of gas-liquid two-phase rotating detonation was obtained, and the influences of the axial and circumferential lengths of the combustion chamber on the flow field, detonation wave propagation characteristics and thrust performance of the engine were analyzed. The calculation results showed that the axial length had little effect on the upstream flow field of the combustion chamber, but had a significant effect on the downstream flow field parameters. With the increase of the axial length, the outlet pressure, temperature, density and circumferential velocity of the combustion chamber decreased, while the axial velocity increased gradually, and the average thrust density and fuel specific impulse of the engine increased first and then decreased. When the circumferential length was too short, it was difficult to form a self-sustaining propagating detonation wave in the combustion chamber. As the circumferential length increased, the strength of upstream detonation wave increased, and the corresponding flow field parameters increased, however, the thrust performance of engine decreased slightly.