有压管道充水过程水力特性三维数值模拟

运用Fluent软件建立三维模型,对某调水工程中的一段有压管道充水过程的水力特性进行三维数值模拟计算,采用PISO算法分析了管道充水过程中气体压力、水力要素及两相流流态变化情况。结果表明:充水流量的大小会导致管内气体压力的强烈变化;气体压力变化又会影响进口流速。在水体流到管道后部管壁之前,流线均匀,流态较好;之后气液两相彼此相间,流线错综复杂,流态紊乱,湍流能量较强。建议以"小流量充水原则"对类似输水管道进行试充水操作。

3-D numerical simulation on hydraulic characteristics of water filling process of pressure pipeline

A 3-D numerical simulation on the hydraulic characteristics of the water filling process for a section of the pressure pipeline of a water conveyance project is made with a 3-D model established with the software of Fluent， in which the variations of the air pressure， hydraulic factors and the two-phase flow regime during the water filling process of the pipeline are analyzed with PISO algorithm. The result shows that the magnitude of flow rate is to cause a strong change of the air pressure inside of the pipeline， while the change of the air pressure is to influence the inlet flow velocity. Before the water reaches the wall of the rear part of the pipeline， the streamline is uniform with a better flow regime， and after that， both the air and the liquid phases are interlocked each other with a complicated streamline and stronger turbulence energy. Therefore， it is suggested that it is better to make trial water filling for the similar water conveyance pipeline with the principle of filling with smaller flow rate.