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An Assessment of Comprehensive Code Prediction State-of-the-Art Using the HART II International Workshop DataDespite significant advancements in computational fluid dynamics and their coupling with computational structural dynamics (= CSD, or comprehensive codes) for rotorcraft applications, CSD codes with their engineering level of modeling the rotor blade dynamics, the unsteady sectional aerodynamics and the vortical wake are still the workhorse for the majority of applications. This is especially true when a large number of parameter variations is to be performed and their impact on performance, structural loads, vibration and noise is to be judged in an approximate yet reliable and as accurate as possible manner. In this paper, the capabilities of such codes are evaluated using the HART II Inter- national Workshop data base, focusing on a typical descent operating condition which includes strong blade-vortex interactions. Three cases are of interest: the baseline case and two cases with 3/rev higher harmonic blade root pitch control (HHC) with different control phases employed. One setting is for minimum blade-vortex interaction noise radiation and the other one for minimum vibration generation. The challenge is to correctly predict the wake physics - especially for the cases with HHC - and all the dynamics, aerodynamics, modifications of the wake structure and the aero-acoustics coming with it. It is observed that the comprehensive codes used today have a surprisingly good predictive capability when they appropriately account for all of the physics involved. The minimum requirements to obtain these results are outlined.
Document ID
20120009893
Document Type
Conference Paper
Authors
vanderWall, Berend G. (Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt Brunswick, Germany)
Lim, Joon W. (Army Aviation Systems Command Moffett Field, CA, United States)
Smith, Marilyn J. (Georgia Inst. of Tech. Atlanta, GA, United States)
Jung, Sung N. (Konkuk Univ. Seoul, Korea, Republic of)
Bailly, Joelle (Office National d'Etudes et de Recherches Aeronautiques Meudon, France)
Baeder, James D. (Maryland Univ. College Park, MD, United States)
Boyd, D. Douglas, Jr. (NASA Langley Research Center Hampton, VA, United States)
Date Acquired
August 25, 2013
Publication Date
May 1, 2012
Subject Category
Aerodynamics
Report/Patent Number
NF1676L-13597
Meeting Information
American Helicopter Society 68th Annual Forum and Technology Display(Forth Worth, TX)
Funding Number(s)
WBS: WBS 877868.02.07.07.04.03.01
Distribution Limits
Public
Copyright
Other