Abstract:
Summary.--The distribution of velocity potential difference has been calculated for a thin flat plate in the form of a delta wing at small incidence. The method introduces novel functions with 10 arbitrary constants to expless the doublet distribution over the wing and a special numerical integration to evaluate the downwash at 10 chosen points on the surface. Three different forms of the doublet distribution (a), (b) and (c) are employed and lead to three independent solutions of the resulting simultaneous equations ; solution (c) is considered to be the most accurate. The plan form selected for this investigation is that of a delta wing, of aspect ratio 3, shown in Fig. 1. One object of the laborious calculations is to form the first step towards a fundamental comparison with pressure distributions measured on a model of the wing in the National Physical Laboratory Duplex Wind Tunnel. Solution (c) has been compared with two solutions of the identical problem by vortex-lattice theory as given in R. & M. 2596, Tables 37 and 38 (Falkner, 1948), using respectively 6 and 8 simultaneous equations, viz., solutions 33 and 34 of which the latter involves an auxiliary function P to allow for discontinuities at the median section.
