A CLASS OF AIRFOILS HAVING FINITE TRAILING-EDGE PRESSURE-GRADIENTS

Some new developments relevant to the design of single-element airfoils using potential flow methods are presented. In particular, the ramifications of the unbounded trailing-edge pressure gradients generally present in the potential flow solution for the flow over an airfoil are examined, and the conditions necessary to obtain a class of airfoils having finite trailing-edge pressure gradients are developed. The incorporation of these conditions into the inverse method of Eppler for the design of low-speed airfoils is discussed, and a design generated using the modified scheme is presented for consideration. A detailed viscous analysis of this airfoil demonstrates a significant reduction in the strong viscous-inviscid interactions generally present near the trailing edge. These reductions offer the possibility of improved airfoil performance, as well as the possibility of improved accuracy in the methods of airfoil design and analysis.