Flow Numerical Simulation And Rapid Development Of Centrifugal Pump Impeller With Splitting Blades

Low specific speed centrifugal pump is widely applied in various fields of national economy. But it has the disadvantages of low efficiency, easy to be overloaded under large flow rate condition, and unstable head flow curve and so on. In order to solve these problems, adopting splitter blades between two long blades is one of the most effective methods. Though splitter blades can improve the performance of centrifugal pumps, the mechanism of splitter blades have not been mastered by researchers. In addition, the design parameters of centrifugal impeller with splitter blades are influenced by many factors and a mature system design is not yet formed. The traditional irrigation design is depend on experience, so its development needs long cycle and high costs and it is difficult to adapt to fierce competition in the market.In order to solve these problems, reverse engineering, numerical simulation of CFD and performance tests are adopted to study the centrifugal pumps with splitter blades. Based on a good splitter blade impeller, high performance low specific speed centrifugal pumps can be developed easily, the product development cycle can be effectively shorten and it also can reduce the cost of impeller design. These have strong practical value in engineering. At the same time, analysis of internal flow combination of experimental research, numerical simulation and a good splitter blade impeller has important value to explore the internal flow mechanism and the affect on pump performance about splitter blades. It also has a strong value for future research and optimization. The main work and achievements are as follows:The model studied is an IS 80-50-200 pump. Under the ideological guidance in the reverse engineering, the date of impeller is measured by ATOS mobile optical scanner and the three-dimensional model of pump impeller is reconstructed by CATIA. In this process, involving data measurement method, the point cloud preprocessing and model reconstruction method are learned, some skills of reconstruction model are summarized. Then according to reverse remodeling with a splitter blade centrifugal pump impeller, created impeller flow model and designed a matched Spiral-shaped volute.Then reconstruction model is simulated by FLUENT. Ten groups different flow are computed and the internal condition about velocity and pressure of rated are detailed analysis. Besides, the contrastive analysis of the relative velocity and pressure distribution is carried out to three different condition of flow. In this process, the influence of splitter blades on the flow within impellers and the law of velocity and pressure distribution of internal flow about the centrifugal pump impeller with splitter blades are preliminary disclosed. The result is that: The flow from simulation coincided with the theory analysis; in the standard working conditions, the flow is steady; Splitter blades can improve the performance of centrifugal pumps obviously. But, in some working conditions, there are some unstable phenomenon such as impeller import has the area of negative pressure; In the volute, some part of flow areas especially in the throat exist impact phenomenon and so on. For these, some improvements are proposed.In addition, performance prediction was carried out in centrifugal pumps. Comparing the calculation results and text results, it's obvious that parameters variation is consistent on the whole. Performance texts verified the validation of the performance prediction result of centrifugal pumps based on numerical simulation. But the value between calculation and text is deviated to some extend, the reason of the difference has been analyzed in the dissertation.