Abstract: Fluid-structure interaction (FSI) of gas-liquid two-phase flow in the horizontal pipe is investigated numerically in the present study. The volume of fluid model and standard k-ε turbulence model are integrated to simulate the typical gas-liquid two-phase flow patterns. First, validation of the numerical model is conducted and the typical flow patterns are consistent with the Baker chart. Then, the FSI framework is established to investigate the dynamic responses of the interaction between the horizontal pipe and gas-liquid two-phase flow. The results show that the dynamic response under stratified flow condition is relatively flat and the maximum pipe deformation and equivalent stress are 1.8 mm and 7.5 MPa respectively. Meanwhile, the dynamic responses induced by slug flow, wave flow and annular flow show obvious periodic fluctuations. Furthermore, the dynamic response characteristics under slug flow condition are maximum; the maximum pipe deformation and equivalent stress can reach 4 mm and 17.5 MPa, respectively. The principal direction of total deformation is different under various flow patterns. Therefore, the periodic equivalent stress will form the cyclic impact on the pipe wall and affect the fatigue life of the horizontal pipe. The present study may serve as a reference for FSI simulation under gas-liquid two-phase transport conditions.

Key words: gas-liquid two-phase flow, volume of fluid model, fluid-structure interaction (FSI), dynamic response characteristics

摘要： 本文对水平管内气液两相流下管道流固耦合动态响应特性进行了数值研究。将VOF多相流模型与标准k-ε湍流模型相结合，模拟了水平管内典型的气液两相流流型。首先，对数值模型进行了验证，数值模拟得到的气液两相流型与Baker流型图吻合较好。然后，建立了流固耦合数值模拟框架来研究水平管道与气液两相流相互作用的动力学响应。结果表明，分层流动条件下的动力响应相对平缓，管道最大变形和等效应力分别为1.8 mm和7.5 MPa。同时，段塞流、波浪流和环形流引起的动力响应呈现出明显的周期性波动。此外，段塞流条件下的动态响应特性最大，管道的最大变形和等效应力分别可达4 mm和17.5 MPa。最后，在不同的气液两相流型下，管道总变形的主方向是不同的。总的来说，周期性等效应力会对管壁形成循环冲击，影响水平管的疲劳寿命。本研究可为气液两相输运条件下管道流固耦合动力响应特性的数值模拟提供参考。

关键词: 气液两相流，VOF模型，流固耦合，动态响应特性