叶轮流道结构对双流道泵性能的影响

从叶轮流道结构变化的角度研究双流道泵的内部流场及其流动特性．采用标准k-ε湍流模型和全隐式多网格耦合算法,对双流道泵叶轮的3种流道结构，即上圆弧式（方案a）、直线式（方案b）、下圆弧式（方案c）进行全流道三维不可压缩湍流流场的数值模拟,并比较其在相同工况下的水力性能,探寻最优的双流道泵叶轮流道结构．结果表明：不同叶轮流道结构的双流道泵,在设计工况下的内部压力和速度场分布呈现出规律性和差异性；方案a和方案c的有效流道体积均增大，方案a无阻塞性能最好；方案a的水力效率最低,但在流道出口处具有更加明显的压力降；方案c具有最高的水力效率,扬程最低；综合分析，方案b具有最高扬程14.46 m和较高水力效率78.24%，较另外2种方案，方案b的综合性能指标最优，认定其为最优双流道泵叶轮流道结构.

Influence of impeller passage structure on performance of double channel pumps

From the perspective of structural changes of impeller passage, the internal flow field in double channel pumps and flow characteristics were studied. Standard k-ε turbulent model and implicit multi grid coupling method were applied to numerically simulate the three dimensional inner turbulent flow of the whole passage of three types of pumps (scheme a:up circle type, scheme b:straight line type, and scheme c:down circle type). Under  the same flow rate conditions, hydraulic perfor mance were compared and optimal double channel impeller passage structure were explored between the three types of pump. It was found that different impeller channel structure presented a certain degree of regularity and diversity of velocity & pressure distribution under the design conditions. Efficient proper volume of impeller channel has been increased both in scheme a and scheme c. In comparison, scheme a has the superior non blocking performance and the minimum hydraulic efficiency, with a clear pressure drop at the passage inlet; scheme c has the maximum hydraulic efficiency and the lowest head .Comprehensive analysis of the hydraulic performance and non blocking performance, scheme b with the highest head of 14.46 m and the higher hydraulic efficiency of 78.24%,has superiority,Ana lysis of steady variable condition properly based on numerical simulation and corresponding test verification,scheme b is the optimum structure of impeller passage in double channel pumps.