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The influence of unsteady aerodynamics and inter-blade aerodynamic coupling on the blades responses to harmonic variations of their pitch angles

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 unsteady aerodynamics of a hovering rotor or a rotor in axial flight, named Temura, has been developed in the Technion. This model has succeeded in describing various phenomena of rotor dynamics. In the present paper Temura is used in order to develop a model which describes the blades’ responses to harmonic variations of their pitch angles. This model includes unsteady influences of trailing and shed vortices, together with unsteady geometric effects which represent a special capability of Temura. The model is general and can be applied to any number of blades and arbitrary differences between the pitch angle variations of different blades. The application of the model to analyse cases of collective harmonic pitch variations and differential harmonic pitch variations is presented. Numerical results of the new model are compared with experimental results from the literature and good agreement is shown.

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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