Complex Aerodynamic Design of a Gas Turbine Multistage Axial Compressor Using Multilevel Mathematical Models

The paper presents the results of end-to-end aerodynamic design of a two-stage low-pressure axial compressor with high aerodynamic loading. The design included steps of initial parameter selection on the basis of Smith diagram, design calculation on the average diameter, design calculation on the height, calculation of characteristics and selection of the most promising variant. Next, we performed a working process refinement, first using manual geometry modification methods and then using automated optimization methods. During the initial design, several compressor variants were created in parallel, differing in flow path shape as well as flow rate coefficients. Thus, the initial design was performed in a wide search area. Further fine-tuning was performed for the most promising variant at the expense of a small correction of the shape of flow paths and blade rows, i.e. the design was carried out in a narrow area of search. As a result of fine-tuning the workflow using manual geometry changes, either the compressor stability margin or the efficiency was achieved, but not both at the same time. Automated optimization using IOSO software resulted in both the required stability margin and compressor efficiency.