Session: 01-05 Inlet Distortion and Engine Operability I

Paper Number: 124697

124697 - Numerical and Experimental Investigation of Steady Flow Distortion in Drooped Turbofan Intakes 

In some civil aero engines, steady flow distortion in turbofan intakes is often caused by the non-axisymmetric geometry, mostly droop and scarf, and the trend of shortening nacelle exacerbates this distortion. Much analysis of previous research has established models for numerically predicting the propagation of modes through the region of steady flow distortion, but experimental measurements of the internal flow field in the intake remain challenging. The main objective of this paper is to demonstrate the feasibility of experimentally investigating the steady flow distortion in drooped turbofan intakes, providing a framework for a deeper understanding of the flow mechanisms in these intakes. Firstly, based on two types of geometrical shape, droop and scarf, three different geometries of intakes are designed, and the steady flow distortion they generate are compared. Notably, the scarf-type intake exhibited significant separation. By using an optimization approach based on a two-dimensional panel method, improvements are made to the design of the intake lip, effectively controlling the separation in the scarf-type intake. Based on the CFD results mentioned above, this study designs compressor experiments under static inlet conditions. The experiments are conducted on an aspirated compressor, and total pressure and static pressure measurements are recorded with 5-hole Aero-Probe. The research results indicate that both droop and scarf type intakes cause minor steady flow distortion at the outlet of the intake, and this steady static pressure distortion rapidly decays in the duct. The compressor experiment is successful in capturing this steady flow distortion.

Presenting Author: Yuhan Zhang Beihang University

Presenting Author Biography: Zhang Yuhan received his bachelor's degree from Beihang University, Beijing, China, in 2022. He is currently a Ph.D. student in Research Institute of Aero-engine at Beihang University. He is majoring in Aerospace Propulsion Theory and Engineering. His research interests focus on inlet/engine compatibility and axial compressor flow stability.

Authors:

Yuhan Zhang Beihang University
Xu Dong Beihang University
Zhenyu Li Beihang University
Dakun Sun Beihang University
Xiaofeng Sun Beihang University