Session: 31-07 Compressor Off-Design Impacts & Stall Inception

Paper Number: 128643

128643 - Sensitivity Analysis for Flow Stability of Axial Compressor Based on Meridional Flow 

The safe operating range of the compressor is threatened by the demands of higher thrust-to-weight ratio for aero-engines and resulting higher pressure ratio for compressors. For decades, engineers have been working hard to extend the safe operating range of the compressor and a large quantity of flow control approaches are proposed to meet the requirement of stability margin. However, how to theoretically guide the design of these approaches has always been a focus and difficult issue. Aiming at estimating the unstable regions, revealing possible mechanisms of the stall inception of the axial compressor and developing a method to guide the design of the engineering applications used to enlarge the stall margin, such as the casing treatment and the blade shape construction, a sensitivity analysis method for flow stability based on the meridional flow of the compressor is proposed in the present work. The meridional model transforms the stability problem into an eigenvalue problem and can predict the stall margin accurately. By selecting the growth rate of the perturbations as the targeted parameter and introducing the adjoint method and boundary conditions, the sensitivity analysis method based on the meridional flow is developed and could be utilized to analyze the sensitive regions in the flow field. A typical case named Rotor 37, and a low-speed axial compressor stage in Beihang University named TA36, are selected as the objects of study. The inception of the rotating stall can be predicted accurately based on the stability prediction model and the outcomes of the sensitivity analysis for the flow parameters reveal that, the rotating stall is sensitive to the base flow field at the blade tip region of the compressor, especially the flow structures at the leading edge of the rotor blade. Meanwhile, analysis for the sensitivity of the stall margin to the blade forces reveals that the blade loading at the tip region could have a significant impact on the operating range of the compressor. The capability of the theoretical method proposed in the present work to identify the stability sensitivity positions could effectively guide the design of the flow control methods.

 

Presenting Author: Haoyu Ni School of Energy and Power Engineering, Beihang University

Presenting Author Biography: English Name: Peter
A Ph. D student in Beihang University, majoring in flow stability problem in axial compressor.
The supervise teacher is Pro. Dakun Sun.

Authors:

Haoyu Ni School of Energy and Power Engineering, Beihang University
Yibo Fang Beijing Institute of Astronautical Systems Engineering
Dengke Xu School of Energy and Power Engineering, Beihang University
Hengyi Zhu School of Energy and Power Engineering, Beihang University
Dakun Sun School of Energy and Power Engineering, Beihang University
Xiaofeng Sun School of Energy and Power Engineering, Beihang University