气液同轴喷嘴缩进室动态特性均相流模型

采用频率法对气液同轴喷嘴缩进室内气液两相流动态特性进行了分析.采用均相流模型,在把液相介质参数看作集中参数的条件下讨论了缩进室边界压降振荡对液相质量流量振荡的动态响应.通过对模型喷嘴算例编程进行计算,结果表明:随着扰动频率的增加,缩进室两端压降振荡的振幅增大,压降振荡与液体流量振荡之间的相位差也增大.较小长径比的缩进室以及较小的液体喷嘴质量流量、大气液比和高反压可以抑制缩进室边界压降振荡.

Investigation on dynamic characteristic of recessed region of a gas-liquid coaxial injector with homogeneous flow model

The dynamic characteristic of gas-liquid two phase flow in the recessed region of a gas-liquid coaxial injector was investigated with the frequency method. Considering the liquid-phase as a lumped-element, the dynamic response of the pressure drop fluctuation in the recessed region to the liquid flow fluctuation was calculated with the homogeneous flow model. The dynamic characteristic of the injector models were calculated. The calculation results showed that the amplitude of pressure drop fluctuation and the phase-delay between the pressure drop fluctuation and liquid flow fluctuation will increase as the fluctuation frequency increases. A smaller length to diameter ratio recessed region and liquid injector mass flow, or a higher ambient pressure and larger gas to liquid ratio can depress the pressure drop fluctuation in the recessed region.