Publication

Abstract : The tandem airfoil configuration (TAC) has various notable advantages such as reduction in span of wing, structural weight, and parasitic drag. It also increases the total lift of the aircraft. Experimental or computational study observations were made in earlier works at low Reynolds number associated with low Mach numbers or high Reynolds number in the transonic regime. In this work, a 2D CFD analysis is conducted where the TAC is studied at transonic, low-Reynolds-number flows. Such flows occur at high altitudes of around 30 km for stealth UAVs planned by the military. Such situations also occur at low altitudes in the Martian atmosphere. The aerodynamic effects of airfoil shape on TAC are observed primarily using two airfoils, Wortmann fx63137-il (low-Reynolds-number airfoil) and RAE 2822 (transonic airfoil). Our simulations show that low-Reynolds-number effects are found to be dominant in the low transonic Mach regime (0.7–0.8) where Wortmann FX 63-137 shows good aerodynamic efficiency, but as we move to higher transonic Mach numbers (>0.8), RAE 2822 showed better aerodynamic efficiencies for the cases tested.