氢气占比对氢气-煤油-空气旋转爆轰波传播特性的影响

为研究燃料中氢气占比对旋转爆轰波传播特性的影响,以液态煤油和氢气作为燃料、空气为氧化剂,通过求解Navier-Stokes方程对旋转爆轰过程进行二维数值模拟.通过改变质量流量和燃料中氢气的占比对旋转爆轰波进行二维数值模拟,研究不同工况对旋转爆轰波传播特性的影响,并对燃烧室内新爆轰波形成过程、模态转换过程和气液分布不均匀...

The Influence of Hydrogen Proportion on the Propagation Characteristics of Hydrogen-kerosene-air Rotating Detonation Waves

The influence of hydrogen proportion on the propagation characteristics of rotating detonation waves is studied. Two-dimensional numerical simulation of rotating detonation process was made by solving the Navier-Stokes equation，in which liquid kerosene and hydrogen were used as fuel，and air was used as oxidant. The influence of different working conditions on the propagation characteristics of rotating detonation wave is studied by changing the mass flow rate and the proportion of hydrogen，and the formation process of new detonation wave，the mode conversion process and the mal-distribution of gas and liquid in the combustion chamber are analyzed. Numerical results show that the detonation wave has three propagation modes，namely single wave mode，single wave mode caused by double wave collision and double wave mode caused by double wave collision，under the successful detonation condition. The double wave mode is easily generated by increasing mass flow rate and hydrogen proportion，and the propagation velocity of rotating detonation wave suddenly decreases when propagation mode changes from single wave to double wave. At the end of the first propagation period of detonation wave， the weak shock wave generated during the initial ignition collides with the detonation wave and transmits it. A hot spot is induced by the transmitted shock wave near the slow-burning area and forms a new detonation wave. After a series of collisions，transmitting，and enhancing processes，a stable single wave mode or double wave mode is finally formed. When the detonation wave stabilizes，the internal flow field during the stable propagation of rotating detonation wave in the combustion chamber can be divided into slow-burning area，combustion-rich area，oxygen-rich area and filling area due to the mal-distribution of gas and liquid in the combustion chamber.The formation of hot spots near the slow-burning area is one of the reasons for the formation of new detonation wave.