Implicit LES; Laminar separation bubble; Variational multiscale method; Accurate prediction; Aero-dynamic performance; Low Reynolds number; Reference data; Skin friction distribution; Test case; Transition mechanism; Variational multiscale methods; Chemical Engineering (all); Physics and Astronomy (all); Physical and Theoretical Chemistry
Abstract :
[en] The accurate prediction of Laminar Separation Bubbles (LSBs) is crucial for understanding transition mechanisms and aerodynamic performance of airfoils operating at low Reynolds numbers. This study employs the Linearized and Segregated Variational Multiscale (VMS) Method to simulate LSB formation and development on airfoils. The methodology is validated against two well-documented test cases: SD7003 airfoil, and the E387 airfoil at,. The results demonstrate strong agreement with reference data from the literature, accurately capturing pressure and skin friction distributions as well as velocity profiles associated with LSB dynamics. To further assess the method’s predictive capability, simulations are performed on a DU89-134 airfoil, designed for High Altitude Pseudo Satellites (HAPS) applications at,, 5∘. Comparisons with experimental vertical velocity profiles - obtained with hot-wires anemometry - show excellent agreement, confirming the method’s robustness in transitional flow modelling. These findings highlight the effectiveness of the Linearized and Segregated VMS approach for Large Eddy Simulations of LSBs. The method provides a reliable tool for aerodynamic analysis of low-Reynolds-number airfoils, with potential applications in next-generation high-altitude flight vehicles.
Brunelli, Carlo; MECA, Royal Military Academy, Brussels, Belgium ; Engineering Technology, Vrije Universiteit Brussel, Brussels, Belgium ; Aeronautics and Aerospace, von Karman Institute for Fluid Dynamics, Sint-Genesius-Rode, Belgium
Avirovic, Matija; MECA, Royal Military Academy, Brussels, Belgium ; Aeronautics and Aerospace, von Karman Institute for Fluid Dynamics, Sint-Genesius-Rode, Belgium ; Faculty of Engineering and Architecure, Department of ElectroMechanical, Systems and Metal Engineering, Ghent University, Gent, Belgium
Janssens, Bart; MECA, Royal Military Academy, Brussels, Belgium
Marinus, Benoît G.; MECA, Royal Military Academy, Brussels, Belgium
Hillewaert, Koen ; Université de Liège - ULiège > Aérospatiale et Mécanique (A&M) ; Aeronautics and Aerospace, von Karman Institute for Fluid Dynamics, Sint-Genesius-Rode, Belgium
This research has been financed by the Royal Higher Institute for Defense for funding this research through the project MSP21/02 Numerical and Experimental Low Speed High Altitude Wing (NELSHAW).
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