ABSTRACT

A 3D computational fluid dynamics model based on a volume of fluid (VOF) approach is presented to simulate air-water interactions and transient pressures in T-junction pipes of urban stormwater drainage system. The effective heat transfer due to compressible air pocket, and various k-ε and k-ω turbulence models, are considered to account for the potential energy attenuation during air-water interactions. One effective meshing method considers the boundary layer of the pipe wall and the effect of grid density. The proposed approach with RNG model can accurately reproduce the experimental pressure oscillations, including the pressure peaks and periods and the pressure damping, and is importantly helpful to explore the complicated flow characteristics. Rapid filling of T-junction pipe with trapped air undergoes: (a) with the air movement and expulsion in vertical pipe, but without any geyser; or (b) involving the air movement and expulsion in vertical pipe, accompanying the violent geyser.

摘要

提出了一种基于流体体积 (VOF) 方法的 3D 计算流体动力学模型，用于模拟城市雨水排水系统 T 型接头管道中的空气-水相互作用和瞬态压力。由可压缩气穴和各种k-ε和k-ω湍流模型引起的有效热传递被认为是空气-水相互作用过程中潜在能量衰减的原因。一种有效的网格划分方法考虑了管壁的边界层和网格密度的影响。建议使用RNG 的方法模型可以准确再现实验压力振荡，包括压力峰值和周期以及压力阻尼，对探索复杂的流动特性有重要帮助。截留空气快速填充 T 型接头管道经历： (a) 空气在垂直管道中运动和排出，但没有任何间歇泉；或 (b) 涉及垂直管道中的空气运动和排出，伴随着猛烈的间歇泉。