| Water pump are used extensively in people's life, but they account for a lot ofelectric power. For a long time, they have a shortcoming of low efficiency.Traditionarily, there are some methods such as reducing the impeller, amending andreplacing the impeller and adding ceramics in impeller, but every method have its`weakness.Living beings optimized itself continuously by self-adapt, self-study,self-organization and self-breed through aeon. It formed very firm and adapting tooutside system surface configuration by long-time optimization. Non-smoothsurface have been found by study on surface of creature living in water such anshark and dolphin, which can change structure and velocity distribution of flowboundary layer close to flow field of object surface to stabilize the boundary layer,keep from the swift for laminar flow to overfall and make the water drag to reduceobviously. According to this point, the author carried on process and experiment onbionic non-smooth impeller of centrifugal water pump which had been usedextensively in water pump industry in order to increase its efficiency.Due to the strongpoint such as high rotate speed, small volume, light weight,high efficiency, large flow rate, reliable function, simple operation, easymaintenance and so on, centrifugal water pumps are used more and more extensively.The author selected 200QJ50-26 centrifugal water pump from Jilin Fangtian waterpump factory as smooth model. The author designed nine non-smooth models bychoosing configuration and shape of the non-smooth unit, the diameter of unit itselfand the distance between two adjacent non-smooth units as experimentalfactors, Based on the orthogonal experimental design testing. These models wereprocessed by TG-5400 metal decaying and carving machine in Chang-chun metaldecaying and carving factory. In Key Laboratory of Terrain-machine BionicsEngineering (Jilin University), Ministry of Education, water pump experimentalsystem was set up. By the experiment system, hydraulic pressure, flow rate, voltageand current in 30 flow rate points of every model were measured. From these date,the author computed the efficiency of every flow rate points.The major and minor factors influencing efficiency in every flow rate point andthe optimal levels of factors were gotten by range and variance analysis of results.According to statistical principle, the author got two regular flow rate segments, Themajor and minor factor of the first segment is C,D,A,B, the optimum combinationis A3,B1,C2,D2。The major and minor factor of the second segment is C,B,D,A, the optimum combination is A1,B3,C1,D2。By efficiency and efficiency increased rate analysis, the highest efficiencyincreased is 3.23% and the lowest is -4.17% in the first segment. The highestefficiency increased is 3.45% and the lowest is -2.79% in the second segment. Thehighest efficiency increased rate is 17.00%, the lowest is -26.18% in the firstsegment. The highest efficiency increased rate is 6.68%, the lowest is -5.63% in thesecond segment. From above, some regularity can be seen that some models withsurface of bionic non-smooth design have obviously effect.At last, the author carried on computer simulation on the smooth model and theoptimum models. From result of the simulation, the distribution of pressure andvelocity are gotten for the smooth model, which provides the reference for thefurther study on bionic non-smooth water pump. The shear stress and the skinfriction coefficient velocity and flow line are also gotten for the optimum models.
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