湍流模型对水轮机压力脉动数值预测的比较  

Comparison of numerical simulation of pressure pulsation in Francis hydraulic turbine by different turbulence models

作　　者：钱忠东[1] 杨建东[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,武汉430072

出　　处：《水力发电学报》2007年第6期111-115,共5页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金资助项目(50609020);湖北省自然科学基金杰出青年人才项目(2006ABB040);水资源与水电工程科学国家重点实验室开放研究基金资助项目(2004C006)

摘　　要：分别采用大涡模拟模型、标准k-ε模型和Realizablek-ε模型,对模型水轮机全流道内的三维非定常湍流进行了数值模拟,对导水机构及尾水管内的湍流压力脉动进行分析,并与试验结果比较。分析结果表明:大涡模拟方法对湍流脉动的大尺度分量进行直接模拟,对强旋流有很好的适应性,能够较准确预测水轮机的压力脉动;Realizablek-ε模型考虑了流体微团转动的影响,可定性分析水轮机全流道的压力脉动特征;标准k-ε模型忽略了流体微团转动的影响,对水轮机压力脉动的模拟结果误差较大。The three dimensional simulation of turbulent flow in the whole flow passage of model hydraulic turbine is conducted by using large eddy simulation（LES） with standard k-ε turbulence model and realizable k-ε turbulence model. The pressure pulsation in the draft tube and wicket gate is predicted and compared by with experimental one. The analyzed results show that large scale components are simulated directly by LES, it is suitable for rotating flow and can predict pressure pulsation in hydraulic turbine accurately; the tensor of rotation is included in the realizable k-ε turbulence model, so it can be used for qualitative analysis of rotating flow and pressure pulsation; the tensor of rotation is not included in the standard k-ε turbulence model, so the computational result of pressure pulsation by standard k-ε turbulence model has obvious deviation.

关 键 词：水力机械 压力脉动 数值模拟 混流式水轮机 湍流模型 

分 类 号：TK730.2[交通运输工程—轮机工程]