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Updated: Jul 13, 2026
09:58
Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
Towards transition modelling for supersonic laminar flow control based on spanwise periodic roughness elements.
Meelan Choudhari1, Chau-Lyan Chang, Li Jiang
1NASA Langley Research Center, Hampton, VA 23681, USA. meelan.m.choudhari@nasa.gov
Summary
This study explores passive laminar flow control using leading edge roughness to stabilize supersonic airflow over swept wings. Findings advance quiet and efficient supersonic aircraft design by managing boundary layer instabilities.
Area of Science:
- Aerospace Engineering
- Fluid Dynamics
- Supersonic Flight
Background:
- Laminar flow control (LFC) is crucial for efficient and quiet supersonic aircraft.
- Passive LFC using leading edge roughness is a novel concept developed at Arizona State University (ASU).
- This method aims to suppress crossflow instabilities in swept-wing boundary layers.
Purpose of the Study:
- To develop an engineering methodology for designing and optimizing roughness-based supersonic LFC.
- To investigate the receptivity and development of stationary crossflow instabilities.
- To provide canonical findings for a holistic prediction approach to transition.
Main Methods:
- Investigated stationary crossflow instabilities on a Mach 2.4, 73-degree swept airfoil.
- Analyzed receptivity, linear, and nonlinear development stages of instabilities.
- Utilized a canonical flow configuration for detailed study.
Main Results:
- Reported canonical findings on receptivity and instability development.
- Characterized the behavior of crossflow instabilities under specific supersonic conditions.
- Provided foundational data for roughness-based LFC design.
Conclusions:
- The ASU concept shows promise for passive laminar flow control in supersonic regimes.
- Understanding receptivity and instability development is key for effective LFC design.
- Further development of integrated prediction methods is needed for practical application.
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