用积分变换法分析周向不对称射流的稳定性问题

Analysis of Azimuthal Instability of Two-Phase Jets by Integral Transformation

该文以喷射雾化过程中气体喷嘴的分布特性造成的射流不稳定性为研究对象,建立了描述射流周向变化的双流体模型,将射流截面的周向不对称性作为截面形状的高阶小量,代入到扰动的方程中处理.受射流界面周向不对称性的影响,在扰动的边界条件中会出现非齐次项.作者采用对扰动的方程和边界条件进行积分变换的方法对其进行处理,得出了频率与波数的色散关系,进而分析了各参数的变化对射流稳定性的影响.

A two-fluid model is constructed to study the azimuthal instability in two-phase jets caused by asymmetric distribution of nozzles in the process of spray atomization. The azimuthally asymmetric term of the gas-liquid interface is supposed to be much less than the nozzle＇s radius. This results in a nonhomogeneous term in the perturbed boundary conditions when the normal mode method is applied in the present study. A Fourier-Laplace integral transformation method is used to solve the linear equation and obtain a dispersion relation analytically. Finally, the influence of different flow parameters on the instability characteristics is discussed.