Aerodynamic Analysis of a Curved-Channel ABLE Airfoil in Hypersonic Rarefied Flow

An airfoil, equipped with a curved-channel artificial blunted leading edge (ABLE), is a good alternative to increase the lift-to-drag ratio. For this purpose, a curved-channel ABLE was applied to a diamond airfoil to analyze the aerodynamic performance in high-altitude hypersonic rarefied flow. The drag reduction and lift increment efficiency of the ABLE airfoil were analyzed in the hypersonic rarefied flow at angle of attack of 0 ~ 10°. The variation in the aerodynamic performance of the ABLE airfoil with partial channel configurations was determined using the direct simulation Monte Carlo (DSMC) method. The results showed that with suitable ABLE configuration and parameter values, the concept of ABLE can help reduce the drag coefficient, improve the lift coefficient, and obtain a better lift-to-drag ratio without considerable aerothermal tradeoff. However, the drag reduction effect of the curved-channel airfoil in the rarefied flow is much lower than that in the continuous flow, because the increased wetted area will increase the viscous drag obviously. The overall aerodynamic performance is significantly deteriorated because of the rarefaction effect of the atmosphere.