Formation of stabilized oblique detonation waves in a combustor
Formation of stabilized oblique detonation waves in a combustor
复制标题
DOI：
10.1016/j.combustflame.2020.09.034
复制
发表时间：
2021
影响因子：
4.4
通讯作者：
Zijian Zhang;C. Wen;Wenshuo Zhang;Yunfeng Liu;Zonglin Jiang
中科院分区：
文献类型：
--
作者：
Zijian Zhang;C. Wen;Wenshuo Zhang;Yunfeng Liu;Zonglin Jiang
斜爆轰波的起爆和稳定对斜爆轰发动机的成功应用具有重要意义，但在实际燃烧室条件下对其进行研究的还很少。本文通过求解具有详细氢燃烧机理的二维多组分雷诺平均守恒方程，对典型氢燃料常压常压燃烧室的流动结构、稳定特性和潜在推力性能(在不同的燃烧室几何形状和不同的奇波反射位置下)进行了数值研究。结果表明，在空间受限的燃烧室中，爆轰波/激波都可以稳定，而由奇波-边界层相互作用引起的边界层分离是决定燃烧室燃烧模式类型的关键。燃烧室中可能同时存在由稳定过驱法向爆轰波(NDW)引起的快速燃烧(甚至在很大程度上达到了73.7%)。结果表明，超驱动NDW在燃烧室中的稳定可以归因于形成了一个有效的气动收敛-扩张喷管，该喷管能迅速将NDW后面的亚音速流动加速到超音速，阻止下游扰动向上游传播。得益于流动膨胀效应引起的化学平衡移动，可以释放更多的热量来补偿压缩损失，即使在ODE燃烧室中存在很大比例的NDW诱导燃烧，模拟的推力性能也没有明显恶化。这项工作将有益于《诗经》的未来发展。
Initiation and stabilization of oblique detonation waves (ODWs) are important to the successful application of oblique detonation engines (ODEs), which, however, have been rarely studied under realistic combustor conditions. In this study, the flow structures, stabilization characteristics and potential thrust performance (under different combustor's geometries with different ODW reflection locations) in a typical hydrogen-fueled ODE combustor are numerically studied by solving the two-dimensional multi-species Reynolds-averaged conservation equations with a detailed hydrogen combustion mechanism. Results suggest that all the detonation waves/shock waves can be stabilized in the space-confined combustor, and the boundary layer separation induced by the ODW-boundary layer interaction is found crucial to determining the types of combustion mode in the combustor. Except for the expected ODW-induced combustion, fast combustion induced by a stabilized overdriven normal detonation wave (NDW) may exist in the combustor simultaneously (even up to a large extent, >73.7%). It is demonstrated that the stabilization of the overdriven NDW in the combustor can be attributed to the formation of an effective aerodynamic convergent-divergent nozzle that quickly accelerates the subsonic flow behind the NDW to supersonic, preventing downstream disturbances from propagating upstream. Benefiting from the chemical equilibrium shift caused by the expansion effect of the flow, more heat is released to compensate for the compression loss and the simulated thrust performance is shown not deteriorate significantly even with a large percentage of NDW-induced combustion existing in the ODE combustor. This work would be beneficial to the future developments of the ODEs.