Numerical Study of Long Separation Bubble on Slotted Thick Airfoil

Abstract

Larbi Tebessi, Route de constantine 12002 TebessaThis work is aimed to examine the potential of two types of slots to control the long laminar separation bubble LoSB developed on the suction side of the thick symmetric NACA0021 airfoil. Two dimensional simulations are carried out under steady state and incompressible regime with the correlation-based intermittency turbulent model in order to predict the boundary layer transition aspect. Two slots are included separately in the airfoil and are proposed as a passive tool to manipulate the LoSB under the effect of pressure gradient between both high and low pressurized zones. The results without control are confronted with experimental data and give a good validation. Concerning the controlled configurations, the transversal slot fails to manipulate the LoSB, while the longitudinal slot reveals its positive potential to control the LoSB and therefore enhancing the lift coefficient of the airfoil and the length of the SB, however, the drag coefficient was increased.

Improving the Aerodynamic Performance of WIG Aircraft with a Micro-Vortex Generator (MVG) in Low-Speed Condition

“…The best configuration is found to be 127.5 • and with a vortex frequency of 35 Hz. The micro-vortex generator (MVG) (vane-type and ramp-type) [22], bump [23,24], slot [25], and oscillating cylinder [26] are common approaches that are introduced in the case of passive flow control. Meanwhile, Syahin et al [5] investigated the communication of MVG, using a micro-ramp, with the drag coefficient on WIG.…”