蜗壳结构对液力透平径向力的影响  

Influence of volute configurations on radial force of hydraulic turbine

作　　者：杨军虎[1] 李泰龙 

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050

出　　处：《排灌机械工程学报》2015年第8期651-655 680,共6页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(51169010);"十二五"国家科技支撑计划项目(2012BAA08B05);甘肃省教育厅导师基金资助项目(0278)

摘　　要：为研究蜗壳结构对液力透平径向力的影响,以某化工厂XWT 500-18型液力透平为研究对象,采用SST k-ω湍流模型和边界层网格,对单蜗壳、双蜗壳匹配同一叶轮的液力透平进行内部流场数值模拟.根据数值计算结果对比分析2种不同蜗壳结构液力透平的外特性、压力分布、径向力特性.结果表明,在全工况内,单、双蜗壳透平的水头、轴功率接近,双蜗壳结构并无性能优势;双蜗壳结构由于隔板的存在使得叶轮进口附近的静压分布不如单蜗壳的均匀;在最优工况点下,单蜗壳透平的径向力最小,约为双蜗壳的一半,双蜗壳液力透平的径向力水平大于单蜗壳液力透平,双蜗壳液力透平径向力平衡较差;单、双蜗壳液力透平径向力方向与隔舌夹角在小流量下变化较大,在大流量下变化较小.分析结果可对液力透平径向力的认识和蜗壳设计提供参考.In order to study the influence of the volute configurations on the radial force of the hydraulic turbine,the XWT 500- 18 type hydraulic turbine in a chemical plant was selected as the research object. The SST k- ε turbulent model and the boundary layer grid were used to simulate hydraulic turbine with various volutes of single volute,double volute,in which the same impeller was adopted. The performance characteristics,pressure distribution and radial force of the hydraulic turbine with two different volutes were compared and analyzed according to the simulated results. The results show that the head and shaft power of single volute turbine are close to those of double volute turbine in all conditions. There is no advantage of performance in double volute turbine. The distribution of static pressure near the inlet of double volute impeller is less uniform than that of single volute impeller due to the existence of the diaphragm. The radial force of the optimal point of the single volute turbine is the minimum which is half as large as that of double volute turbine. The radial force of the double volute turbine is higher than that of the single volute turbine overall while its balance is much poor. The direction and spiral angle of two kinds of turbines change greatly at small flow rates while its range is smaller at bigflow rates. The results of the analysis can provide the reference of the understanding of the radial force and volute design in hydraulic turbine.

关 键 词：液力透平 单蜗壳 双蜗壳 径向力 数值模拟 

分 类 号：TQ051.21[化学工程]