Mean Line Performance Calculation And Optimization Of Multi-stage Axial Compressor

Mean line performance calculation plays an important role inquasi-three dimensional design system of compressors. Design projectscan be chosen quickly by integration of mean line method andmulti-objective optimization algorithm, and we can predict theperformance of compressors. It is widely used in compressor design.On the basis of discussing principle of mean line method, efficiencyprediction model and deviation angle prediction model are modifiedaccording to the design and experiment data of a10-stage transoniccompressor. Mass flow method and stall pressure rise method are built asstall margin prediction model. The performance of inlet stage, outlet stagesof core compressors and a whole compressor is predicted by the modifiedprogram. The result shows that the modified program has high accuracy inpredicting total pressure ratio and total efficiency of compressors.Secondly, mean line method and multi-objective optimizationalgorithm are integrated. The design point performance of two multi-stagecompressors is optimized. The design parameters which have highsensitiveness are chosen by DOE. Total pressure ratio and total efficiencyof compressors are goal of optimization. And good optimization result ofdesign point is received. The off-design performance of optimizationproject is compared with that of original project. The result shows thattotal pressure ratio and total efficiency of optimization project at bothdesign point and off-design point are higher.Finally, total dynamic performance of10-stage transonic compressoreffected by variable stators is investigated. There are two parts: the first one is mean line performance compare and analysis of different variablecases by adjusting single variable stator; the second one is optimization ofthe rule by adjusting all variable stators with mean line method andmulti-objective genetic algorithm, which is multi-point and multi-objective(total efficiency and stall margin). The result shows that a reasonablevariable rule would improve total dynamic performance of compressorseffectively.