Flow visualization and hot wire measurements were made on a 0.08-scale model of the XV-15 tiltrotor in hover. Both a full-span configuration and a semi-span configuration with an image plane were investigated. Rotor-inflow velocities and fountain flow velocities at a rotor azimuth of 270 deg were compared on the two configurations. Although mean inflow velocities were the same over most of the rotor span, important flow field differences were measured in the fountain-flow region. The aperiodic lateral shifting of the fountain flow causing intermittent turbulence ingestion by the rotors was prevented on the semi-span model. Also, the fountain flow was higher on the semi-span model, and the fountain turbulence was recirculated farther inboard, because of a high-velocity wall jet formed on the image plane. Finally, rotor inflow turbulence levels were higher on the semi-span model because of additional vorticity production in the boundary-layer formed on the image plane.
Effects of an image plane on the tiltrotor fountain flow
Einfluß einer in der Symmetrieebene angebrachten Trennwand auf die von den Schwenkrotoren eines Drehflügelflugzeugs induzierte Strömung
Journal of the American Helicopter Society ; 45 , 2 ; 90-96
2000
7 Seiten, 10 Bilder, 3 Tabellen, 30 Quellen
Aufsatz (Zeitschrift)
Englisch
Effects of an Image Plane on the Tiltrotor Fountain Flow
Online Contents | 2000
|British Library Conference Proceedings | 1999
|British Library Conference Proceedings | 1995
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