Affordable and Accurate Numerical Predictions of Helicopter Rotor Noise in Forward Flight

Authors

  • Tugrul Teoman Ozturk Istanbul Technical University, Faculty of Aeronautics and Astronautics, 34469, Istanbul, Türkiye
  • Alim Rüstem Aslan Istanbul Technical University, Faculty of Aeronautics and Astronautics, 34469, Istanbul, Türkiye

Keywords:

Rotor, Helicopter, CFD, URANS, HART II

Abstract

In the present work, a numerical methodology is
developed for affordable and accurate analysis of
helicopter rotor noise in forward flight. The flow
field is obtained using unsteady compressible
flow analyses using commercially available
computational fluid dynamics (CFD) solver
FLUENT. Azimuthal variations of the flap and
pitch motions of the blades are prescribed a
priori as high order polynomial equations
through a user-defined function. The rotor noise
is predicted using Fluent Acoustic module based
on the Ffowcs-Williams and Hawking's equations.
Methodology is verified using HART II
experimental setup and data which includes
flapping, pitching, lead-lag motion and elastic
torsion for each rotor blade. Individually defined
blade motion is found critical for an accurate
acoustic prediction based on the obtained CFD
calculation. The present predictions compare
very well and performs better than other
previous CFD analysis both for minimum noise
and baseline case at maximum sound pressure
level (SPL) of HART II data, even with meshes of
7-8 million cells rather than tens of millions
usually needed.

Downloads

Download data is not yet available.

References

United States. Government Accountability Office, Better Information Sharing Could Improve Responses to Washington, D.C. Area Helicopter Noise Concerns. Report on GAO-21-200. 2021. [Online]. Available: https://www.gao.gov/products/gao-21-200. [Accessed: Dec. 12, 2023].

United States. LII. Electronic Code of Fedaral Regulation (e-CRF) Noise Requirements For Helicopters Under Subpart H. Corner Law School: 2001. [Online] Available: https://www.law.cornell.edu/cfr/text/14/appendix-H_to_part_36. [Accessed: Dec. 12, 2023].

Wikipedia. ”Aircraft noise pollution”. Available: https://en.m.wikipedia.org/wiki/Aircraft_noise_pollution [Sept. 10, 2023].

Wikipedia. ” Health effrects from noise”. Available: https://en.m.wikipedia.org/wiki/Health_effects_from_noise [Sept. 10, 2023].

O. Schneider, B. G. Van der Wall ,“Institute Report IB 111-2003/07 Preparation of SPR Data from HART II “ German Aerospace Center (DLR) Braunschweig, January 24th , 2003.

K. Brentner and F. Farassat, Modeling Aerodynamically Generated Sound of Helicopter Rotors, Progress in Aerospace Sciences 39(2), 83–120 (2003).

National Aeronautics and Space Administration (NASA). B. Edwards C. Cox. Revolutionary Concepts for Helicopter Noise Reduction-S.I.L.E.N.T. Program, Nasa Technical Reports Server-NASA/CR-2002-211650; 2002. [Online]. Available: https://ntrs.nasa.gov/citations/20020051150. [Accessed: Dec. 12, 2023].

National Aeronautics and Space Administration (NASA). F.B. Metzger. A Review of Propeller Noise Prediction Methodology 1919-1994, NASA Contractor Report 198156; 1995. [Online]. Available: https://ntrs.nasa.gov/citations/19960008819. [Accessed: Dec. 12, 2023].

M. V. Lowson, The sound field of singularities in motion., Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences 286(1407), 559-572 (1965).

S. E. Wright, Sound radiation from a lifting rotor generated by asymmetric disc loading, Journal of Sound and Vibration 9(2), 223–240 (1969).

M. V. Lowson, J. B. Ollerhead, A theoretical study of helicopter rotor noise, Journal of Sound and Vibration 9(2), 197–222 (1969).

J. E. Ffowcs Williams and D. L. Hawkings, Sound Generation by Turbulence and Surfaces in Arbitrary Motion, Philosophical Transactions of the Royal Society of London. Series A. Mathematical and Physical Sciences 264(1151), 321–342 (1969).

M. J Smith, J.W Lim, B.G van der Wall,. et al, The HART II international workshop: an assessment of the state of the art in CFD/CSD prediction. CEAS Aeronaut Journal 4, 345–372 (2013).

J. W. Lim and A. C. B. Dimanlig, “The Effect of Fuselage and Rotor Hub on Blade-Vortex Interaction Airloads and Rotor Wakes.” in 36th European Rotorcraft Forum, Paris, France, September 7-9, 2010. Paper Number: 051.

J. W. Lim, A. Wissink, B. Jayaraman, and A. Dimanlig: “Helios Adaptive Mesh Refinement for HART II Rotor Wake Simulations.” in Annual Forum 68 of the American Helicopters Society Annual Forum 68, Fort Worth, Texas, Aerodynamic Session May 1-3, 2012. pp:440-463.

M. E. Kelly, K. Duraisamy and R. E. Brown, “Predicting Blade Vortex Interaction, Airloads and Acoustics using the Vorticity Transport Model “in the AHS Specialists’ Conference on Aeromechanics, San Francisco, CA, Jan. 23-25, 2008. (The American Helicopter Society International, 2008.

B. G. Van der Wall. “Mode identification and data synthesis of HART II blade defection data“, in Institute Report IB-111-2007/28, Braunschweig, Germany, Jul. 2, 2007. DLR-Interner Bericht. Institute of Flight Systems. DLR-IB 111-2007/33. 48 S.

Y. Tanabe. S. Saito, S. Hideaki., “Construction and Validation of An Analysis Tool Chain For Rotorcraft Active Noise Reduction”, 38th European Rotorcraft Forum, 235-247 (2012).

M. B Açıkgöz, A.R. Aslan, Dynamic Mesh Analyses of Helicopter Rotor Fuselage Flow Interaction in Forward Flight. Journal of Aerospace Engineering 29(6), (2016).

G. Romani and D. Casalino, Rotorcraft blade-vortex interaction noise prediction using the Lattice-Boltzmann method, Aerospace Science and Technology 88, 147-157 (2019).

B.G. Van der Wall. L.B. Casey “2nd HHC Aeroacoustic Rotor Test (HART II) Part II: Representative Results “ Institute Report IB 111-2005/03 (2005).

Ansys/Fluent 19.2 User Guide Item 8.1.6 “Influencing Body” (2019). Available: https://users.abo.fi/rzevenho/ansys%20fluent%2018%20tutorial%20guide.pdf. [Accessed: Dec. 12, 2023].

B. G. Van der Wall, Institute Report IB 111-2003/31 “2nd HHC Aeroacoustic Rotor Test (HART II) Part I:” Test Documentation Braunschweig, Germany (2003).

Ansys/Fluent 12.0 User Guide Item 12.3.1. “Wall functions” (2009). Available: https://www.afs.enea.it/project/neptunius/docs/fluent/html/ug/main_pre.htm. [Accessed: Dec. 12, 2023].

G. Wilke, “Efficient Aero-Acoustic Simulation of the HART II Rotor with the Compact Pade Scheme“. 42nd European Rotorcraft Forum, German Aerospace Center (DLR) Braunschweig, Germany Sept. 6, 2016. Institute of Aerodynamics and Flow Technology, 2016.

National Aeronautics and Space Administration (NASA). R. E Mineck, S. A., Gorton. Steady and periodic pressure measurements on a generic helicopter fuselage model in the presence of a rotor, Nasa Technical Reports Server- NASA/TM-2000-210286; 2013. [Online]. Available: https://ntrs.nasa.gov/citations/20000057579. [Accessed: Dec. 12, 2023].

W. Sutherland, The viscosity of gases and molecular force, Philosophical Magazine 5(36), 507–531 (1893).

S. J. Park, S. N. Jung, et. al, Validation of comprehensive dynamics analysis predictions for a rotor in descending flight, Aircraft Engineering and Aerospace Technology 83(2), 75-84 (2011).

R. Steijl, G. Barakos, and K. Badcock, A framework for CFD analysis of helicopter rotors in hover and forward flight, International Journal for Numerical Methods in Fluids. Methods Fluids 51(8), 819–847. (2006).

Ansys Fluent 19.2 User Manual item 2.6.4, “Grid Motion” (2019). Available: https://users.abo.fi/rzevenho/ansys%20fluent%2018%20tutorial%20guide.pdf. [Accessed: Dec. 12, 2023].

National Aeronautics and Space Administration (NASA). F. Farassat. Derivation of Formulation 1 and 1A of Farassat, Nasa Technical Reports Server- NASA/TM-2007-214853; 2007. [Online]. Available: https://ntrs.nasa.gov/citations/20020051150. [Accessed: Dec. 12, 2023].

National Aeronautics and Space Administration (NASA). Acoustic Noise Requirement, Preferred Reliability Practices, Practice No: Pd-Ed-1259, 1996. [Online]. Available: https://www.klabs.org/DEI/References/design_guidelines/design_series/1259. pdf. [Accessed: Dec. 12, 2023].

Downloads

Published

29-01-2024

How to Cite

[1]
T. T. Ozturk and A. R. Aslan, “Affordable and Accurate Numerical Predictions of Helicopter Rotor Noise in Forward Flight ”, JAST, vol. 17, no. 1, pp. 205–255, Jan. 2024.

Issue

Section

Articles