Calculation And Analysis About Inside Flow Field And Performance Prediction For Submersible Axial Flow Pump

Submersible axial flow pumps are widely used now, not only because it has the characters of the general axial pump, but also it has else several advantages such as examination and repair convenient, structure simple, and so on. However, the efficiency of submersible axial flow pump which made in our country is lower about 5-15% than the foreign ones. Through analyzing, it is showed that the major factors which influence the performance of the pump are the shape of axial section flow channel, the hydraulic parameter of impeller and guide blade and the geometric parameter of the inlet conduit. Therefore, it is very important to research deeply in the rule of flow field inside submersible axial flow pumps and the suction box, which can improve the performance and upgrade the design level of the pump.The standard k- ε turbulence model and SIMPLEC algorithm are applied to analyze the full flow passage of the ZQ2870C-4 submersible axial flow pump and the suction box by FLUENT6.1 in this thesis. The main conclusions are as follows:There is a low-pressure area near the inlet edge of suction surface, and it will take place cavitation at this region, which agrees well with the actual situation;the distribution of pressure on working surface of vane is not perfect, the profile of the vane should be improved. There is great flow impact on the head of vanes at different condition, and it will affect the performance of pump system greatly, so the shape of the head of vanes should be improved. Toward the guide blade, the distribution of pressure near the outlet of guide blades is not good, the analysis results show that the shape of axial section flow channel is not reasonable, and it should be improved.By analyzing the calculation of the suction box at different value of Hw and Hj, we can draw the conclusions: the height of the conduit (Hw) takes 1.8D0, which not only makes the flow condition inside the suction box good, but also avoid the construction difficulties and wasting of the investment;toward the inlet height of the conduit (Hj) takes 1.6D0, and this value has great significance in designing the suction box.For verifying the veracity of calculational data, this paper predicted the performance of ZQ2870C-4. It can conclude that the tendency of the predicted curve agrees well with the experiment curve basically, the error of forecast date is little at the design condition.