叶片厚度对低比转数离心泵性能的影响

为了研究叶片厚度对低比转数离心泵性能的影响,选取一比转数为48的离心泵为研究对象.在离心泵其他几何参数给定的条件下,通过改变圆柱形叶片厚度,构造了5种不同叶片厚度的叶轮.基于标准k-ε湍流模型,采用SIMPLE算法,在6种不同工况下分别对其进行全流场数值模拟,对比分析了叶片厚度对泵的外特性及内部流场的影响,得出了叶片厚度对泵水力性能的影响规律.结果表明:叶片厚度在一定范围内,随着叶片厚度的增大,泵的最优工况点向小流量偏移,最高效率略有提高;同时随着叶片厚度的增加,泵在设计工况下运行时的湍动能损失不断增大;在满足叶片结构强度的前提下,选取合理的叶片厚度,可确保离心泵具有较好的水力性能.

Effects of blade thickness on performance of low-specific-speed centrifugal pump

In order to research the effects of blade thickness on the performance of a low-specific-speed centrifugal pump, a centrifugal pump with a specific speed of 48 was selected as a study object. With other geometric parameters fixed, five kinds of impellers with different blade thickness of a centrifugal pump were constructed. Based on the standard k-ε turbulence model and SIMPLE algorithm, numerical simulation was performed by commercial software Fluent under six different operation conditions. The relationship between the blade thickness and the hydraulic performance was analyzed from the external characteristics and internal flow. The results have shown that when the blade thickness increases in a certain range, the best efficiency point of the pump moves to the small flow direction and the top efficiency increases slightly. Additionally, the internal turbulence energy loss increases gradually under the design condition. Under the prerequisite of having meet the blade structural strength, selecting appropriate blade thickness could ensure the better hydraulic performance of a centrifugal pump.