Loss Sources and Magnitudes Breakdown in an Axial Low Pressure Compressor Blade Row

Abstract

The transition to more environmentally friendly and economically efficient aircraft engines involves a reduction of aerodynamic loss inside compressors. On the one hand, a qualitative breakdown enables to identify, understand and separate the different loss sources. On the other hand, a quantitative breakdown can be used for design iteration loop and trade-off study.

A decomposition of loss in terms of sources or mechanisms is chosen based on existing papers in the literature. The decomposition of loss sources is used as basis for the qualitative breakdown. Each source is related to existing models for the computation of the corresponding loss magnitude. Focusing on two-dimensional loss through a single row with a very basic blade geometry and with a subsonic inlet mach number, the existing models are compared to each other. Profile boundary layer loss, wake mixing loss and profile shock loss models are computed and related to the overall reference. The reference loss is computed from Computational Fluid Dynamics. The results are used to perform the quantitative breakdown. The total pressure loss corresponding to each loss source is plotted for different inlet mach numbers. The corresponding loss percentage for each source is also computed.

This work is expected to be extended to a general tool for preliminary design stages of compressors. The main limitations come from the assumptions, the simulations conditions and the error due to the interaction between the wake integration and the passage shocks. The perspectives for future works are the use of more representative blade geometries and flow conditions while also expanding the scope of the work to three-dimensional loss computation.