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The influence of unsteady aerodynamics andinter-blade aerodynamic coupling on the bladesresponses to harmonic variations of their pitchangles

Published online by Cambridge University Press:  04 July 2016

A. Rosen ,
A. Isser  and
M. Yoshpe
A. Rosen
Affiliation:
Technion — Israel Institute of Technology, Haifa, Israel
A. Isser
Affiliation:
Technion — Israel Institute of Technology, Haifa, Israel
M. Yoshpe
Affiliation:
Technion — Israel Institute of Technology, Haifa, Israel
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Abstract

During recent years a new vortex model of the unsteadyaerodynamics of a hovering rotor or a rotor in axialflight, named Temura, has beendeveloped in the Technion. This model has succeededin describing various phenomena of rotor dynamics.In the present paper Temura is usedin order to develop a model which describes theblades’ responses to harmonic variations of theirpitch angles. This model includes unsteadyinfluences of trailing and shed vortices, togetherwith unsteady geometric effects which represent aspecial capability of Temura. Themodel is general and can be applied to any number ofblades and arbitrary differences between the pitchangle variations of different blades. Theapplication of the model to analyse cases ofcollective harmonic pitch variations anddifferential harmonic pitch variations is presented.Numerical results of the new model are compared withexperimental results from the literature and goodagreement is shown.

Information

Type
Research Article
Information
The Aeronautical Journal , Volume 100 , Issue 991 , January 1996 , pp. 27 - 35
Copyright
Copyright © Royal Aeronautical Society 1996 

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