Retreating side helicopter blades often experience stall when flying at high speeds or at high thrusts. There are a number of consequences to stall which result in significant increases in blade stresses, vibration levels, pitch link loads and required shaft power. The prediction of these effects is at present still unsatisfactory. The models used in existing aeroelastic codes often lack accurate details of stall phenomena and rarely account for the effects of rotation on stall. This paper presents some of the results and conclusions of a GARTEUR action group concerning stall effects and blade torsion. Seven different prediction models are described and tested against detailed measurements on a model rotor in a wind tunnel. In order to identify the physical phenomena needing most attention in future developments, a series of calculations is carried out for a flight condition with a high load factor. These predictions use a range of hypotheses and models. In this procedure the unsteady stall models used are evaluated with respect to experimental 2D hysteresis loops. Conclusions are drawn relative to the state-of-the-art of dynamic stall models and of rotor calculations in general.
Stall effects and blade torsion - an evaluation of predictive tools
Überziehwirkungen und Rotorblattverdrehung - Eine Bewertung von Vorhersagetools
1997
11 Seiten, 4 Bilder, 13 Quellen
Aufsatz (Konferenz)
Englisch
Stall Effects and Blade Torsion - An Evaluation of Predictive Tools
Online Contents | 1999
|Stall effects and blade torsion - An evaluation of predictive tools
Tema Archiv | 1999
|Stall Effects and Blade Torsion - An Evaluation of Predictive Tools
British Library Conference Proceedings | 1997
|Emerald Group Publishing | 1942