Abstract: A nonlinear physical model to probe into driving mechanism of combustion instability in rocket engine was presented.The nonlinear relation between combustion and acoustic process was studied. The mathematics model was deduced from the basic control equations for reaction fluid dynamics.“Averaging Method”was used to analyze the mathematical equations. Bifurcation and chaos were found in this nonlinear system.The effects of physical parameters on the combustion instability with this physical model was discussed.

Key words: Liquid propellant rocket engine;Combustion stability;Nonlinear vibration;Mathematical simulation

摘要： 为探讨火箭发动机高频燃烧不稳定的机理 ,建立了不稳定燃烧非线性物理模型 ,研究燃烧速率对燃烧室的波动现象非线性反馈机制 ,简化气相化学反应流体力学控制方程组 ,得到了相应的数学模型。用“平均法”分析数学模型和仿真的结果表明 ,系统在一定的参数范围内发生复杂的分岔和混沌现象 ,并得到各种物理参数对燃烧与波动耦合产生燃烧不稳定现象的影响规律。

关键词: 液体推进剂火箭发动机;燃烧稳定性;非线性振动;数学仿真