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A full-span free-wake model using circular-arc vortex elements and incorporating rotor trim analysis

Hu, G.H. and Newman, S.J. (2006) A full-span free-wake model using circular-arc vortex elements and incorporating rotor trim analysis Journal of Aerospace Engineering, 220, (2), pp. 145-163. (doi:10.1243/09544100G04704).

Record type: Article


An analytical method incorporating a free-wake analysis with a rotor trim algorithm is developed for predicting rotor wake geometry and blade loading distribution for a helicopter in hover and forward flight. The wake model of this method is based on a multi-filament full-span free wake, using sophisticated circular-arc vortex elements. The blade model is based on the second-order lifting-line theory to improve the calculation of three-dimensional tip effects. A rotor trim method is given, based on the finite-difference approximation of the blade flapping motion and the trim Jacobian matrix. This is subsequently coupled into the free-wake model. In order to demonstrate the capability of the coupled method, comparisons between the calculated results and the available experimental data of the rotor blade flapping motion for a model rotor are presented covering conditions from hover through forward flight. The free-wake geometry and the blade loading distribution at a low advance ratio are calculated for the H-34 helicopter rotor, and the blade loading distribution is compared with both the measured data and calculated results on the basis of the undistorted wake.

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Published date: April 2006
Keywords: free wake, vortex element, rotor, trim analysis, helicopter


Local EPrints ID: 44003
ISSN: 0954-4100
PURE UUID: d096816e-1a8b-4b29-bacc-b65da8cc59a3

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Date deposited: 07 Feb 2007
Last modified: 17 Jul 2017 15:16

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Author: G.H. Hu
Author: S.J. Newman

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