Aerodynamic Design And Optimization Of A Micro-centrifugal Compressor

Due to its compact structure,high single-stage pressure ratio and axial exhaust,the micro-centrifugal compressor is widely used in many fields.The preliminary work of developing a series of micro-centrifugal compressors has carried out.According to the design requirements of a micro centrifugal compressor,the preliminary design of the compressor and the construction of the experimental bench are carried out.The performance and internal flow field of the compressor are analyzed in detail through experiments and numerical calculations.Multi-objective optimization of the pre-designed compressor is carried out.The main research contents are as follows:Firstly,according to the design requirements of centrifugal compressor,a heat-dimensional design of compressor is carried out,and a one-dimensional computation computation is compiled.Based on the one-dimensional design,three-dimensional design is compiled.After the preliminary design is completed,the experimental bench construction and low-speed experiment are carried out,and some performance curves of the compressor are obtained.Secondly,the performance of the preliminary design of the centrifugal compressor and the numerical simulation of the internal flow field are carried out by using NUMECA software.According to the calculation results,the predicted performance curves of the compressor under different flow rates are drawn,and the internal flow field of the compressor is analyzed in detail.Lastly,in order to improve the pressure ratio and isentropic efficiency of the compressor,the compressor is optimized.In the impeller,One-dimensional and three-dimensional optimization design are carried out.Firstly,BP neural network and genetic algorithm are combined to optimize the one-dimensional multi-objective of the impeller,and the Pareto solution set is obtained through MATLAB.Secondly,based on the one-dimensional optimization,the impeller is optimized in three dimensions by Design3 D software.In the diffusers,the number of blades of the diffuser is adjusted.Numerical analysis of the optimized compressor is carried out using NUMECA software.The results show that the performance of compressor has also been greatly improved.In the design working condition,the total pressure ratio of the compressor has been increased to 2.45,the isentropic efficiency has been increased to 0.73,and the stable working range has also been significantly expanded.Compared with the prototype,the high Mach number area of the impeller inlet disappears,butthe outlet still has a large flow loss diffuser part.Diffusers’ flow loss is greatly reduced,the total pressure and static pressure of the outlet have increased.