大型尾水调压室底部交汇型式CFD分析与优化

多机共用尾水调压室的底部管道交汇型式对调压室布置和运行时流态和水头损失有重要影响,是设计中需认真对待的问题。为研究交汇型式与水头损失的规律性并为工程设计提供参考,本文应用最新计算流体动力学技术对一系列交汇型式进行了以减小水头损失为主要目标的分析、优化。首先介绍了数学模型和计算方法;然后通过与典型流道水头损失经验公式和具体工程模型试验数据对比来验证计算模型;在确认模型精度的基础上,对两机共用一室、三机共用一室的各种可能交汇型式的水头损失系数和水流流态进行比较分析,给出优化的体型;最后总结体型优化的规律,指出交汇型式设计中应注意的事项。

Optimization of the converging type of conduit of tailrace surge tank by CFD method

The converging type or shape of conduits of tailrace surge tank of multi-unit system is of important influence on flow conditions and head losses,therefore it deserves atterntion in design.To study the relationship between converging type and head loss as well as to provide reference data for the design of projects,a series of possible types are analyzed and optimized by using the newest computational fluid dynamics(CFD) method.After an introduction to the mathematical model and numerical scheme,the feasibility of CFD is verified by comparing the simulation results of head losses of some typical conduit structures and practical converging types with model test or empirical data.Then detailed simulations and analysis of flow patterns and head losses for some typical two-unit-appreaching-one-tunnel and three-unit-approaching-one-tunnel converging types are carried out. Finally,the general rules of type optimization and guidelines of design practice are emphasized.