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http://dx.doi.org/10.5139/JKSAS.2019.47.7.489

Airloads and Structural Loads Analysis of LCH Rotor Using a Loose CFD/CSD Coupling  

Lee, Da-Woon (Dept. of Mechanical & Aerospace Engineering, Seoul National University)
Kim, Kiro (Dept. of Aerospace Information Engineering, Konkuk University)
Yee, Kwan-Jung (Dept. of Mechanical & Aerospace Engineering, Seoul National University)
Jung, Sung-Nam (Dept. of Aerospace Information Engineering, Konkuk University)
Publication Information
Journal of the Korean Society for Aeronautical & Space Sciences / v.47, no.7, 2019 , pp. 489-498 More about this Journal
Abstract
The airloads and structural loads of Light Civil Helicopter (LCH) rotor are investigated using a loose CFD/CSD coupling. The structural dynamics model for LCH 5-bladed rotor cwith elastomeric bearing and inter-bladed damper is constructed using CAMRAD-II. Either isolated rotor or rotor-fuselage model is used to identify the effect of the fuselage on the aeromechanics behavior at a cruise speed of 0.28. The fuselage effect is shown to be marginal on the aeromechanics predictions of LCH rotor, though the effect can be non-negligible for the tail structure due to the prevailing root vortices strengthened by the fuselage upwash. A lifting-line based comprehensive analysis is also conducted to verify the CFD/CSD coupled analysis. The comparison study shows that the comprehensive analysis predictions are generally in good agreements with CFD/CSD coupled results. However, the predicted comprehensive analysis results underestimate peak-to-peak values of blade section airloads and elastic motions due to the limitation of unsteady aerodynamic predictions. Particularly, significant discrepancies appear in the structural loads with apparent phase differences.
Keywords
LCH; CFD/CSD Coupling; Inter-blade Damper; Blade-vortex Interaction; Fuselage Effect;
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