本文以水平微圆管内气液两相环状流气液界面为研究对象,通过分析重力、表面张力和界面剪切力对环状流液膜厚度的影响,重点考虑Rayleigh不稳定性对气液界面的依存关系,得到了不同管径和气核直径变化时不稳定性的变化规律,并分析拟合了最危险波长和气核直径的关联式,为后续建立高热流密度条件下微通道内强化传热理论模型奠定基础. In this paper, the gas-liquid two-phase annular gas-liquid interface in horizontal micro-circular pipe is taken as the research object. By analyzing the influence of gravity, surface tension and interfacial shear force on the thickness of annular liquid film, the Rayleigh instability is mainly concerned with the gas-liquid interface The correlations between instability of different diameter and gas core diameter were obtained. The correlation between the most dangerous wavelength and gas core diameter was analyzed. The results showed that for the subsequent establishment of high heat flux density, Theoretical model laid the foundation.