Analysis and Comparison with Theory of Flow-field Measurements Near a Lifting Rotor in the Langley Full-scale Tunnel

Download or read book Analysis and Comparison with Theory of Flow-field Measurements Near a Lifting Rotor in the Langley Full-scale Tunnel written by Harry H. Heyson and published by . This book was released on 1956 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of an investigation in the Langley full-scale tunnel of the induced flow near a lifting rotor are given. Measurements of stream angles and velocities were made in several transverse planes along and behind the rotor in four different conditions representative of the cruising and high-speed ranges of flight. These measurements indicate that available theory may be used to calculate with reasonable accuracy the induced flow over the forward three-quarters of the disk for these flight conditions provided that a realistic nonuniform rotor disk-load distribution is assumed. Rearward of the three-quarter-diameter point, calculations of the induced velocity are increasingly inaccurate due to the rolling up of the trailing-vortex system. Farther rearward, well behind the rotor, the flow may be represented more accurately by the flow behind a uniformly loaded wing.