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Influence of Helicopter Rotor Wake Modeling on Blade Airload Predictions
Christos Zioutis, Apostolos Spyropoulos, Anastasios Fragias, Dionissios Margaris, Dimitrios Papanikas
Pages - 521 - 537     |    Revised - 30-12-2009     |    Published - 31-01-2010
Volume - 3   Issue - 6    |    Publication Date - January 2010  Table of Contents
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KEYWORDS
Helicopter aerodynamics, rotor wake, vortex core
ABSTRACT
In the present paper a computational investigation is made about the efficiency of recently developed mathematical models for specific aerodynamic phenomena of the complicated helicopter rotor flowfield. A developed computational procedure is used, based on a Lagrangian type, Vortex Element Method. The free vortical wake geometry and rotor airloads are computed. The efficiency of special models concerning vortex core structure, vorticity diffusion and vortex straining regarding rotor airloads prediction is tested. Investigations have also been performed in order to assess a realistic value for empirical factors included in vorticity diffusion models. The benefit of using multiple vortex line to simulate trailing wake vorticity behind blade span instead of isolated lines or vortex sheets, in spite their computational cost, is demonstrated with the developed wake relaxation method. The computational results are compared with experimental data from wind tunnel tests, performed during joined European research programs.
CITED BY (2)  
1 Hegne, A. V., & Hegne, P. Design and Power Transmission of Advanced Light Helicopter.
2 Rodriguez, S. B. (2011). Swirling Jets for the Mitigation of Hot Spots and Thermal Stratification in the VHTR Lower Plenum. 7474, Sandia National Laboratories (available at.
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Mr. Christos Zioutis
University of Patras - Greece
zioutis@mech.upatras.gr
Mr. Apostolos Spyropoulos
University of Patras - Greece
Mr. Anastasios Fragias
University of Patras - Greece
Associate Professor Dionissios Margaris
Mechanical Engineering and Aeronautics Department - Greece
Professor Dimitrios Papanikas
University of Patras - Greece