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Free wake analysis of hover performance using a new influence coefficient method
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TLDR
In this paper, a new approach to the prediction of helicopter rotor performance using a free wake analysis was developed, which uses a relaxation process that does not suffer from the convergence problems associated with previous time marching simulations.Abstract:
A new approach to the prediction of helicopter rotor performance using a free wake analysis was developed. This new method uses a relaxation process that does not suffer from the convergence problems associated with previous time marching simulations. This wake relaxation procedure was coupled to a vortex-lattice, lifting surface loads analysis to produce a novel, self contained performance prediction code: EHPIC (Evaluation of Helicopter Performance using Influence Coefficients). The major technical features of the EHPIC code are described and a substantial amount of background information on the capabilities and proper operation of the code is supplied. Sample problems were undertaken to demonstrate the robustness and flexibility of the basic approach. Also, a performance correlation study was carried out to establish the breadth of applicability of the code, with very favorable results.read more
Citations
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References
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Experimental and Analytical Studies of a Model Helicopter Rotor in Hover
F. X. Caradonna,C. Tung +1 more
TL;DR: In this paper, a benchmark test to aid the development of various rotor performance codes was conducted, where simultaneous blade pressure measurements and tip vortex surveys were made for a wide range of tip Mach numbers including the transonic flow regime.
Dissertation
Computation of helicopter rotor wake geometry and its influence on rotor harmonic airloads
TL;DR: In this article, the authors present an approach for the design of an unmanned aerial vehicle (UAV) based on the concept of a self-healing sensor network, which is a technique from aeronautics.
Journal ArticleDOI
A numerical study of the roll-up of a finite vortex sheet
TL;DR: In this article, a point-vortex representation is used to study numerically the evolution of an initially plane vortex sheet and a tip vortex is introduced to represent the tightly rolled portion of the vortex sheet.
ReportDOI
An Analytical and Experimental Investigation of Helicopter Rotor Hover Performance and Wake Geometry Characteristics
TL;DR: In this article, an analytical and experimental investigation was conducted to acquire systematic model rotor performance and wake geometry data and to evaluate the accuracy of various analytical methods in predicting the effects on performance of changes in helicopter rotor design and operating parameters.