The seepage of gas-liquid two-phase flow in fracture is a commonly found phenomenon in nature. To reveal the underlying mechanism and the critical condition of the chaos occurrence, a stochastic gas-liquid two-phase flow seepage model is established, and then investigated through a numerical simulation and a horizontal Hele-Shaw experiment. The numerical simulation and laboratory experiment results show that the seepage chaos of gas-liquid two-phase flow takes place when the relative saturation is in the range of gas relative saturation 44%-70%, and the occurrence probability can be expressed in polynomials. The chaos probability exceeds 80% when the relative saturation of gas is 47%-65%, and the chaos probability is 100% when the relative gas saturation is 57%-60%. It is found that the stochastic variation of gas connection cluster and the compressibility of gas lead to a remarkable change of pressure gradient of the gas-liquid flow both in magnitude and direction. Therefore, the turbulent flow is formed, the kinetic energy of fluid transport decreases gradually, and the flow is stopped at last.

中文翻译：

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单裂缝气液两相混沌流动机理

裂缝中气液两相流的渗漏是自然界普遍存在的现象。为了揭示混沌发生的潜在机制和临界条件，建立了随机气液两相流渗流模型，然后通过数值模拟和水平Hele-Shaw实验进行研究。数值模拟和室内实验结果表明，气液两相流的渗流混沌发生在相对饱和度在气体相对饱和度44%-70%范围内，其发生概率可以用多项式表示。含气相对饱和度为47%-65%时混沌概率超过80%，相对含气饱和度为57%-60%时混沌概率为100%。发现气体连接簇的随机变化和气体的压缩性导致气液流动的压力梯度在大小和方向上都有显着变化。因此，形成湍流，流体输送的动能逐渐减小，最终停止流动。