Lifting Line Theory in Linearly Varying Flow

Citation

Fejér, Andrej (Andrew) (1945) Lifting Line Theory in Linearly Varying Flow. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/EJJN-XF31. https://resolver.caltech.edu/CaltechETD:etd-11202008-133148

Abstract

The problem of a wing placed in a flow that is nonuniform in the spanwise direction is of interest to the aerodynamicist as well as to the designer of rotating machinery. The portion of a wing located in the slip stream of the propeller, the blades of propellers and fans, wind-tunnel models in nonuniform airstreams are some of the examples. Prandtl's three dimensional wing theory assumes a uniform undisturbed flow and thus it is not valid in these cases. Some authors tried to modify Prandtl's theory in order to make it applicable to such problems. The work of F. Vandrey (Ref. 1) and K. Bausch (Ref. 2) may be mentioned in this connection. A discussion of their work is given in Section 7 of Part I of this analysis. Lately Th. von Karman and H. S. Tsien presented a general solution of the problem, of a wing placed in a flow with the velocity varying in both directions normal to and parallel with the wing span (Ref. 3). In the following the author will utilize the results of von Karman and Tsien for the simpler case of the velocity varying linearly and in the direction of the span only and solve the "third problem of airfoil theory" (finding the lift distribution for an airfoil of given shape) for a finite wing in an infinite fluid and for the case of a wing between two parallel walls. The wing in an infinite fluid is treated in Part I while Part II contains the solution of the problem of the wing between walls.

Thesis Files