Effects of the hinge position and suction on flow separation and aerodynamic performance of the NACA 0012 airfoil

Abstract

In the present study, the effect of hinge position (H) has been numerically investigated to find the appropriate position for improving the aerodynamic performance of the NACA 0012 flapped airfoil. In addition, perpendicular and tangential suctions have been applied to control the flow separation and enhance the aerodynamic performance over the NACA 0012 flapped airfoil at each different hinge positions. The simulations were carried out at a Reynolds number of 5 × 10 5 (Ma = 0.021) based on two-dimensional incompressible unsteady Reynolds-averaged Navier-Stokes calculations to determine the adequate hinge position. The turbulence was modeled using the shear stress transport k-ω turbulence model. The effect of perpendicular suction (θ jet = − 90°) and tangential suction (θ jet = − 30°) was computationally studied over NACA 0012 flapped airfoil for five different hinge positions (H = 0.7c, 0.75c, 0.8c, 0.85c and 0.9c) and a flap deflection (δ f) of 15°. Based on the results, the hinge position significantly affects the aerodynamic performance of the airfoil. The lift coefficient increased clearly as the hinge position moved to the trailing edge of the airfoil. Using perpendicular suction caused to increase the lift coefficient and decrease the drag coefficient. Consequently, the maximum value of the lift-to-drag ratio (C L /C D) for perpendicular and tangential suctions was achieved about 35.8% and 25.1% higher than that of the case without suction at an angle of attack of 12° and H = 0.9c. Also, the effect of perpendicular suction was more considerable compared to the tangential suction. This caused a reduction in the size of the recirculation zone from 0.5 to 0.09 of the airfoil chord length and also transferred it from 1.13 to 1.18 of the airfoil chord length.

Simultaneous Effect of Suction and Cavity for Controlling Flow Separation on NACA 0012 Airfoil – CFD Approach

“…Furtheremore, URANS equations are solved with SST k-ω turbulence model. As mentioned in previous researches [14,22,33] of similar flows, SST k-ω demonstrates the good predictive capability for flow having separation which can be written as follows [38]:…”

“…The flow separation control techniques have been considered as a significant field of fluid mechanics [7][8][9][10]. The flow separation control can be achieved employing active methods for example; blowing and suction jets [11][12][13][14], and synthetic jet actuators [15][16][17], or passive methods such as flap, slat, vortex generator, and Gurney flap [18][19][20][21]. Flow simulation around the airfoil up to pre-stall and stall range continues to be a challenging problem and requires experimental results to determine the actual behavior of the flow.…”

Multi-objective aerodynamic optimization design of variable camber leading and trailing edge of airfoil

“…The flowing fluid is considered to be a two-dimensional, turbulent, and viscous incompressible flow. The incompressible RANS equation consists of a continuity equation representing the conservation of mass and a momentum equation representing the conservation of momentum, as follows 20,21…”

Film cooling modeling of a gas turbine blade by considering different injection holes with and without opening angles through CFD

“…Yk and Yω denote the dissipation of k and ω, respectively. Dω is the crossdiffusion term of ω [36,37].…”