A non-overload centrifugal pump has been invented to solve the long-existingoverload problem of low specific speed centrifugal pumps when operating at greater flow andlower head than normal. The performance characteri...A non-overload centrifugal pump has been invented to solve the long-existingoverload problem of low specific speed centrifugal pumps when operating at greater flow andlower head than normal. The performance characteristics of non-overload centrifugal pumpsand the ordinary ones are introduced, and the test results are given here. By I. Khalil's numencalmethod, in hub-shroud plane using potential flow calculation to determine flow surface positionand in blade-blade plane using revised k turbulence model, the inner flow of non-overloadcentnfugal pumps and the ordinary ones are respectively calculated. The numerical simulationshows that the inner flow situates are completely different under the two cases. And there existsremarkable inner flow characteristics of non-overload centrifugal impellers but with neither flowseparation nor apparent wake flow, therefore, the lower efficiency attributes to the larger hydrau-lic friction loss due to larger blade wrapping angle.展开更多
In order to specify the characteristics of un-overloaded centrifugal pumps, the IH100-65-200 pump was chosen as the model pump. Different calculation models for centrifugal pumps were established under different pumpi...In order to specify the characteristics of un-overloaded centrifugal pumps, the IH100-65-200 pump was chosen as the model pump. Different calculation models for centrifugal pumps were established under different pumping chamber sectional parameters. In the numerical simulation of the centrifugal pumps flow field, the shaft power, head, efficiency, and the changes of the internal flow field under different sectional areas and sectional shapes were studied with the RNG k-ε turbulence model, and the influence of the pumping chamber section characteristics of the non-overloaded centrifugal pumps were analyzed. The results show that sectional areas have a significant impact on the non-overload characteristics of centrifugal pumps. The shaft power and head of centrifugal pump are increasing with a lager sectional area, by which the gradient of head curves decreases. The efficiency is improved under a large flow rate condition, but the head and the efficiency are reduced at a small flow rate. It is also observed that the sectional shapes have less influence on the shaft power, the hydraulic performance and flow field characteristics of a centrifugal pump.展开更多
文摘A non-overload centrifugal pump has been invented to solve the long-existingoverload problem of low specific speed centrifugal pumps when operating at greater flow andlower head than normal. The performance characteristics of non-overload centrifugal pumpsand the ordinary ones are introduced, and the test results are given here. By I. Khalil's numencalmethod, in hub-shroud plane using potential flow calculation to determine flow surface positionand in blade-blade plane using revised k turbulence model, the inner flow of non-overloadcentnfugal pumps and the ordinary ones are respectively calculated. The numerical simulationshows that the inner flow situates are completely different under the two cases. And there existsremarkable inner flow characteristics of non-overload centrifugal impellers but with neither flowseparation nor apparent wake flow, therefore, the lower efficiency attributes to the larger hydrau-lic friction loss due to larger blade wrapping angle.
基金Projects(51476144,51305399)supported by the National Natural Science Foundation of ChinaProject(LQ15E050005)supported by the Zhejiang Provincial Natural Science Foundation,China
文摘In order to specify the characteristics of un-overloaded centrifugal pumps, the IH100-65-200 pump was chosen as the model pump. Different calculation models for centrifugal pumps were established under different pumping chamber sectional parameters. In the numerical simulation of the centrifugal pumps flow field, the shaft power, head, efficiency, and the changes of the internal flow field under different sectional areas and sectional shapes were studied with the RNG k-ε turbulence model, and the influence of the pumping chamber section characteristics of the non-overloaded centrifugal pumps were analyzed. The results show that sectional areas have a significant impact on the non-overload characteristics of centrifugal pumps. The shaft power and head of centrifugal pump are increasing with a lager sectional area, by which the gradient of head curves decreases. The efficiency is improved under a large flow rate condition, but the head and the efficiency are reduced at a small flow rate. It is also observed that the sectional shapes have less influence on the shaft power, the hydraulic performance and flow field characteristics of a centrifugal pump.