Julien Deparday
Experimental fluid dynamics. My research and experience.
Archives
Experimental quantification of unsteady leading-edge flow separation
in Journal of Fluid Mechanics, vol. 941, A60, 2022 We propose here a method to experimentally quantify unsteady leading-edge flow separation on aerofoils with finite thickness. The methodology relies on the computation of a leading-edge suction parameter based on measured values of the partial circulation around the leading edge and the stagnation point location. We…
The dynamics and timescales of static stall
in Journal of Fluids and Structures, 104:103304, 2021 Airfoil stall plays a central role in the design of safe and efficient lifting surfaces. We typically distinguish between static and dynamic stall based on the unsteady rate of change of an airfoil’s angle of attack. Despite the somewhat misleading denotation, the force and flow development of…
Stall Delay and Leading-Edge Suction for a Pitching Airfoil with Trailing-Edge Flap
in AIAA Journal, 58(12):5146-5155, 2020 The flow around a pitching NACA0015 airfoil with an oscillating trailing-edge flap is experimentally investigated to characterize the influence of the flap kinematics on the development of dynamic stall. We specifically focus on the timing of the stall development and critical values of the leading-edge suction parameter as potential stall…
Modeling the interplay between the shear layer and leading edge suction during dynamic stall
in Physics of Fluids, 31:107104 , 2019 The dynamic stall development on a pitching airfoil at Re = 106 was investigated by time-resolved surface pressure and velocity field measurements. Two stages were identified in the dynamic stall development based on the shear layer evolution. In the first stage, the flow detaches from the trailing edge…
Critical evolution of leading edge suction during dynamic stall
in Journal of Physics: Conference Series, 1037:022017, 2018 Dynamic stall dominates the aerodynamic performance, the robustness, and the wake dynamics of vertical axis wind turbines. To better assess the dynamic stall onset and its associated unsteady effects, this paper analyzes experimentally the evolution of the leading edge suction vector on a sinusoidally pitching airfoil based…