11/04/2020

Present situation of centrifugal pump performance test



Centrifugal pump performance test
At present, the main problems existing in the operation and actual production of centrifugal pumps and pumping stations are as follows
1. In most cases, the actual working condition of centrifugal pump in pump station often deviates from its design condition, which reduces the operation efficiency electrically.
2. In most of the centrifugal pump stations in China, especially in the pumping stations with large water level variation, the pumping stations often operate under low efficiency conditions, resulting in a large amount of energy waste.
3. Some large flow centrifugal pumps can not be tested in the laboratory.
In order to meet the requirements of water use and the purpose of economic operation, it is often necessary to change the flow rate and head to change the working point. The internal flow analysis of turbomachinery has always been a hot topic. Due to the Coriolis force and centrifugal force caused by the rotation and surface curvature of the impeller, the flow in the impeller is very complex, and often accompanied by flow separation and wake flow. So far, it has not been seen that satisfactory centrifugal pumps have been designed by using the ternary theory.
For a long time, pump manufacturers at home and abroad generally adopt the following procedures for the development of new pumps: first, design several impellers and pump shells, then establish the model, and then put Zui on the test bench, through modification, design, and re test procedures, until the user requirements are met. Therefore, it can predict the characteristic curve of the pump according to the hydraulic parameters such as impeller and volute (guide vane), which obviously can reduce the cost of model making, trial production and test, and shorten the design and manufacturing cycle.
According to the data, 85% of the papers published at the Third International Symposium on wind turbines sponsored by Tsinghua University in 1998 came from colleges and universities and scientific research institutions. Almost no papers were published by major pump manufacturers in China. Compared with foreign countries, the papers published in Germany and Japan are more practical, good at solving the difficult problems of pump users and manufacturers, and also have academic value. Among the papers published in China, there are not many high-level papers which have both practical value and academic significance, and the papers generally lack of practical and guiding significance. This is determined by the current situation of school enterprise cooperation and the current economic environment.
At present, there are several important research directions in pump technology
1. Performance study. 2. Operation and fault diagnosis. 3. Cavitation research. 4. Design and product development. 5、CFD。
Pump design, product development and performance research are endless research directions and hot spots in pump products. These two aspects of research not only belong to the category of applied research, but also can enrich the basic theory and technology of pump, so it is easier to produce results.

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