燃烧室中的非线性声波

Nonlinear acoustic wave in combustors

采用计算流体力学(CFD)方法对燃烧室一维冷流和两维燃烧过程进行了数值仿真,着重研究了温度、密度、熵等变量的脉动与压力脉动的区别,以及喷射过程与声学振型的耦合。结果表明,压力和速度主要表现声特征,温度和密度部分表现声特征,部分表现流特征,而熵则只表现流特征。对于化学反应过程激发的燃烧振荡,最容易受到激发的振型是压力波腹与化学反应分布相关最强的振型。

One and two dimensional combustions in combustors were numerically simulated by Calculation Fluid Dynamics (CFD) . The transmitting processes of temperature pulse, density pulse, entropy pulse, velocity pulse and pressure pulse were studied , and the coupling between the injecting process and acoustic modes was investigated. The results indicate that the transmitting processes of pressure pulse and velocity pulse mainly show acoustic characteristics, while the temperature pulse and density pulse partly show acoustic characteristics, partly show flow characteristics, and the transmitting process of entropy pulse only show flow characteristics. For the combustion instability driven by chemical reactions, the most inspirable acoustic mode is the one whose wave abdomen is the most correlative with chemical reaction distribution.