RT Journal Article ID 731378ed12f79c00 A1 Petrov, Aleksander Sergeevich T1 LIFT AND INDUCED DRAG OF A FINITE-SPAN WING IN A FLOW OF VISCOUS COMPRESSIBLE GAS AT SUBSONIC SPEEDS JF TsAGI Science Journal JO TSAGI YR 2009 FD 2010-07-15 VO 40 IS 5 SP 535 OP 551 K1 lift K1 wing-induced drag K1 compressible viscous gas AB The method of transformation of the law of conservation of momentum for a continuum, applied by Zhukovsky [1] in the derivation of a profile lift theorem in an ideal incompressible fluid, is generalized for a spatial motion of a finite-span wing in a compressible viscous gas. As a result, we obtain an expression for the main vector of aerodynamic forces, which is the analog of the Zhukovsky theorem, but containing the side force and resistance force besides the lift. A correlation between the resistance force and the lift force is shown. An approximate analytical expression for the wing-induced drag in a viscous medium is obtained and the physical nature of its occurrence is studied. Limit as Re→∞, the Prandtl formula is for a wing-induced drag in an ideal fluid. PB Begell House LK https://www.dl.begellhouse.com/journals/58618e1439159b1f,6ab0b2cd52c5749c,731378ed12f79c00.html