Aerodynamic Performance Improvement of the Centrifugal Compressor Employing the Elastic Deformation Theory

Parameterization is a prerequisite for optimizing compressor performance. Traditional parametric methods often require many variables to characterize the geometric shape of the blade, which also increases the computational consumption during the optimization process. This paper introduces a novel method for representing geometry in the optimization workflow of a compressor by employing elastic deformation theory. In order to meet the high-performance demands of a centrifugal compressor, optimization work has been conducted with a focus on enhancing the mass flow rate at the operating point while maintaining the total pressure ratio and efficiency. First, the adjustment of the shroud profile is used as an example to illustrate the detailed approach for geometric generation. The results show significant improvements, with increases of 8.3% in mass flow rate, 1.1% in total pressure ratio, and 1.6% in efficiency. Subsequently, three-dimensional optimization of the blade profile is conducted. The desired configurations are obtained by varying only one variable—the loading force—and performance of the configurations is evaluated through numerical calculation. As a result, there is a remarkable improvement in the mass flow rate, total pressure ratio, and efficiency of the optimized compressor, with increases of 17.4%, 4.2%, and 3.1%, respectively. Furthermore, closer examination of the flow field reveals a correlation between the performance improvement and the flow organization near the blade tip, attributed to shock redistribution. In conclusion, the proposed method is expected to offer more options for geometry optimization, enabling significant enhancements in compressor performance.