长输水管道充水的气液两相流数值模拟

基于缓慢充水过程中管道内气液两相流的流态及其特性,在一系列合理假定的基础上,推导建立了描述充水过程的气液两相流控制方程,给出模型的求解方法和计算流程。采用南水北调工程北京西四环暗涵充水试验数据对模型进行验证,结果表明,数值模型可用于模拟"V"形复杂管道系统缓慢充水过程中管内水流和通气孔气流的两相变化过程。研究成果对长距离输水工程中通气孔、排气阀等调压设施的设计、选型,及后期管道的安全运行、维护管理等具有重要意义。

Numerical simulation on air-liquid two-phase flow for water filling of long distance water conveyance pipeline

Based on the flow pattern of the air-liquid two-phase flow in pipeline during a slow water filling process and its characteristics，a governing equation for describing the air-liquid two-phase flow during water filling is educed and established on the basis of a series of reasonable assumptions，and then the solving method and calculation of the model are given out. The model is verified with the data from the water filling test made for the buried culvert under the West No.4 Ring Road in Beijing of the South-to-North Water Transfer Project. The result shows that this numerical model can be adopted to simulate the two-phase flow changing process of the water flow and the vent-air flow in the pipeline of a V type complicated pipeline system during a slow water filling process. The study result has an important significance for the designs of the pressure regulation devices in the long-distance water conveyance project，such as ventholes，exhause valves，etc. as well as the safety operation，maintenance，management，etc.of the pipeling in the later period.