Data-driven creation of compressor design charts for aeronautical applications

The preliminary design of compressors depends upon a large number of parameters. Initially, the main characteristics and velocity triangles are defined by specifying the flow topology, i.e., whether the compressor is axial, mixed-flow, or centrifugal, the flow coefficient, and the loading coefficient, among other parameters. This paper presents a data-driven approach toward the creation of Smith charts for axial, mixed-flow, and centrifugal compressors on the basis of targeted three-dimensional computational fluid dynamics. The influence of the inlet hub-to-tip ratio, Mach number, the inlet Reynolds number, and the inlet boundary layer thickness on the Smith charts are analyzed. The results are applicable to the design of both single-stage and multi-stage compressors, such as the Mach number, Reynolds number, hub-to-tip ratio, and blockage vary from stage to stage. The compressors designed are then compared to the Cordier diagram. It is shown that the Mach number, Reynolds number, and hub-to-tip ratio significantly influence the Smith charts of compressors and limit the available design space in the Cordier diagram. In addition, changes in the suitable range of specific speeds of the topologies depending on the inlet conditions are shown. The diagrams presented in this paper serve as a guideline for the topology selection based on the flow coefficient and loading coefficient, considering the upstream flow conditions.