Numerical simulation of gas-liquid two-phase flow in horizontal pipeline with different diameters
ZHANG Heming1,2, LI Wenhao1,2, HE Xinlin1,2*, LIU Ningning1,2, JIN Jin 1,2
1. College of Water Conservancy and Architectural Engineering, Shihezi University, Shihezi, Xinjiang 832000, China; 2. Key Laboratory of Modern Water Saving Irrigation Corps, Shihezi University, Shihezi, Xinjiang 832000, China
Abstract：In order to better understand the flow process of gas-liquid two-phase flow in the pipeline, reveal the gas-liquid distribution law and flow pattern in the opaque pipeline, and improve the safety of pipeline self-pressure water conveyance in practical engineering. Based on the existing research results, the numerical simulation of three-dimensional horizontal pipeline was carried out by using Fluent software, and the flow pattern of two-phase flow under different pipe diameter and flow velocity was analyzed, as well as the change of various hydraulic factors such as pressure and flow velocity. The results show that the three-dimensional CFD simulation can better show the distribution of gas-li-quid two-phase in the pipeline, and the flow pattern can be transformed with the increase of the liquid conversion speed. With the increase of the pipe diameter, the transition from bubble flow to plug flow shows higher liquid phase conversion velocity, from less than 4 m/s in 80 mm pipeline to 4 m/s in 160 mm pipeline. With the decrease of liquid conversion speed and pipe diameter, the pressure fluctuation caused by air mass decreases, and the maximum pressure difference at 2.8 m position will decreases from 9 439.2 Pa and 12 826.5 Pa to 9 136.0 Pa. The gradient of velocity decrease on the upper wall of pipeline is higher than that on the lower wall, and the larger the bubble, the more obvious the diffe-rence is. It is considered that if the existence of gas in the process of water delivery cannot be avoided, the pressure fluctuation caused by the air mass will be smaller when the liquid conversion speed and pipe diameter are smaller, and it is considering that the pipeline is safer at this time.
