Method of estimating eighth section area of low specific speed pumps

The performance of volute designed by the method of velocity coefficient is affected by the statistics and designer′s experience.The calculation method of the volute eighth section area in the low specific speed pump is deduced,which is based on the correlation between the impeller and the volute. Four 3-D incompressible flow conditions,which consist of the same impeller and four different volutes respectively,are simulated by using the standard k-e turbulent model and SIMPLE algorithm,and their performance characteristics are also obtained.By verification of corresponding experiment data,a reasonable method in determining the eighth section area is put forward.The pump with this kind of volute can have the best efficiency at the rated flow rate.