Structure Optimization Of Gasoline Engine Electric Compressor Impeller

With the rapid development of the automobile industry,energy shortages and environmental pollution problems are becoming increasingly prominent.Engine booster technology can not only improve the engine power and the economy,but also reduce emissions,so turbocharging technology has been used widely in the car.As the main work parts,the structure of the compressor impeller directly affect the efficiency of the compressor,pressure ratio,the engine fuel economy and emission characteristics and so on.Therefore,many scholars have devoted themselves to the optimization of impeller structure at home and abroad.By using the Computational Fluid Dynamics(CFD),you can obtain the influence of the compressor parameters on the compressor efficiency and pressure ratio quickly and easily,which will provide the theoretical and practical reference value for the compressor blade optimization design.You can also predict the design results,which not only speed up the development cycle,but also reduce the development of risks and costs.Therefore,the use of CFD method for the compressor flow field analysis to optimize the compressor impeller has important significance.This paper takes the compressor of the electric turbocharger as the research object.Firstly,Engine bench test is conducted to study the effect of the compressor on the engine performance.Through the pressure in the engine intake manifold when the engine work in the different throttle opening conditions to understand the actual working characteristic of the compressor.Then,combined with the majority of working condition of the engine,the optimization of compressor speed is determined.The numerical simulation of the compressor was carried out by using the computational fluid dynamics software FLUENT according to the experimental environmental conditions.By analyzing the flow field,it is found that the trend of the flow parameters in the flow field is consistent with the theoretical analysis,and the numerical simulation can reflect the flow state of the gas in the compressor.Based on the original structure of the compressor impeller,the influence of the number of impeller blades,the angle of the inlet of the blade,the combined blades,the blades' shape and the outlet angle of the blades on the compressor pressure ratio were studied by numerical simulation.By analyzing the pressure cloud,velocity vector and fluid tracing of the flow field,it is concluded that the pressure ratio of the compressor is maximum and the compressor has the better performance when the outlet angle in 55°of S-shaped blades.Using the 3D printing technology to put the blade inlet Angle of 10°,14° and different outlet angle of S-shaped blade impeller machining,and build a test bench for static test.The experimental datas show that the compressor that the outlet angle is 55°in the full range of work is higher than the original leaves.