Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-26T01:05:52.620Z Has data issue: false hasContentIssue false

Aeroacoustics of a rotor ingesting a planar boundary layer at high thrust

Published online by Cambridge University Press:  04 July 2018

Henry H. Murray IV*
Affiliation:
Center for Renewable Energy and Aerodynamic Technology, Department of Aerospace and Ocean Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
William J. Devenport
Affiliation:
Center for Renewable Energy and Aerodynamic Technology, Department of Aerospace and Ocean Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
W. Nathan Alexander
Affiliation:
Center for Renewable Energy and Aerodynamic Technology, Department of Aerospace and Ocean Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
Stewart A. L. Glegg
Affiliation:
Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA
David Wisda
Affiliation:
Center for Renewable Energy and Aerodynamic Technology, Department of Aerospace and Ocean Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
*
Email address for correspondence: [email protected]

Abstract

Aeroacoustic measurements and analysis have been made for an unshrouded rotor partially immersed in a planar equilibrium turbulent boundary layer at low Mach number. This configuration provides an idealized model of inflow distortion effects seen when a rotor is mounted adjacent to the hull or fuselage of a vehicle. At low and moderate thrust conditions, the rotor produces broadband noise organized into haystacks produced by large eddies of the ingested turbulence being cut multiple times by successive rotor blades. At high thrust, however, the acoustic signature changes and becomes louder and more tonal. This change is accompanied by separation of the boundary layer from the wall in the vicinity of the rotor blade disk. The separation region is highly unsteady and populated by intense vortex structures. Acoustic analysis suggests that blade–vortex interactions with these structures are the source of the additional tonal noise at high thrust.

Type
JFM Papers
Copyright
© 2018 Cambridge University Press 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alexander, W. N., Devenport, W. & Glegg, S. A. L. 2017 Noise from a rotor ingesting a thick boundary layer and relation to measurements of ingested turbulence. J. Sound Vib. 409, 227240.Google Scholar
Alexander, W. N., Devenport, W., Morton, M. A. & Glegg, S. A. L. 2013 Noise from a rotor ingesting a planar turbulent boundary layer. In 19th AIAA/CEAS Aeroacoustics Conference, May 27–29, Berlin, DE. AIAA 2013-2285.Google Scholar
Amiet, R. K. 1986 Airfoil gust response and the sound produced by airfoil–vortex interaction. J. Sound Vib. 107, 487506.Google Scholar
Atassi, H. M. & Logue, M. M. 2009 Fan broadband noise in anisotropic turbulence. In 15th AIAA/CEAS Aeroacoustics Conference (30th AIAA Aeroacoustics Conference), Miami, Florida, 2009. AIAA 2009-3148.Google Scholar
Awasthi, M. A.2012 High Reynolds number turbulent boundary layer flow over small forward facing steps. Master’s thesis, AOE Department, Virginia Tech, http://theses.lib.vt.edu/theses/available/etd-06292012-120614/.Google Scholar
Blake, W. K. 1986 Mechanics of Flow Induced Sound and Vibration. Academic.Google Scholar
Forest, J.2012 The wall pressure spectrum of high Reynolds number rough-wall turbulent boundary layers. Master’s thesis, Virginia Tech, http://scholar.lib.vt.edu/theses/available/etd-02022012-152048/.Google Scholar
Gavin, J. R. & Lauchle, G. C. 2000 Modeling the timespace correlations in the wake region of a turbulent boundary layer. In Proceedings of ASME Winter Meeting, Orlando, FL, pp. 227234. ASME.Google Scholar
Glegg, S. A. L., Buono, A., Grant, J., Lachowski, F., Devenport, W. & Alexander, W. N. 2015 Sound radiation from a rotor partially immersed in a turbulent boundary layer. In 21st AIAA/CEAS Aeroacoustics Meeting, Dallas, Texas. AIAA 2015-2361.Google Scholar
Glegg, S. A. L. & Devenport, W. 2017 Aeroacoustics of Low Mach Number Flows. Academic.Google Scholar
Glegg, S. A. L. & Walker, N. 1999 Fan noise from blades moving through boundary layer turbulence. In 5th AIAA/CEAS Aeroacoustics Conference. Bellevue, WA. AIAA.Google Scholar
Grace, S. P., Atassi, H. M. & Blake, W. K. 1996a Inverse aeroacoustic problem for a streamlined body. Part 1. Basic formulation. AIAA J. 34, 22412246.Google Scholar
Grace, S. P., Atassi, H. M. & Blake, W. K. 1996b Inverse aeroacoustic problem for a streamlined body. Part 2. Accuracy of solutions. AIAA J. 34, 22332240.Google Scholar
Graham, J. M. R. 1998 The effect of a two-dimensional cascade of thin streamwise plates on homogeneous turbulence. J. Fluid Mech. 356, 125147.Google Scholar
Ganz, U. W., Joppa, P. D., Patten, T. J. & Scharpf, D. F.1998 Boeing 18-inch fan rig broadband noise test. NASA/CR-1998-208704.Google Scholar
Haller, G. 2005 An objective definition of a vortex. J. Fluid Mech. 525, 126.Google Scholar
Hanson, D. 1974 Spectrum of rotor noise caused by atmospheric turbulence. J. Acoust. Soc. Am. 56 (1), 110126.Google Scholar
Hersh, A. S., Soderman, P. T. & Hayden, R. E. 1974 Investigation of acoustic effects of leading-edge serrations on airfoils. J. Aircraft 11, 197202.Google Scholar
Hickling, C. 2017 Efficient beamforming techniques for investigating turbulence ingestion noise with an inhomogeneous inflow. In 23rd AIAA/CEAS Aeroacoustics Conference, Denver, Colorado. AIAA.Google Scholar
Hunt, J. C. R., Wray, A. A. & Moin, P. 1988 Eddies, streams, and convergence zones in turbulent flows. In Center for Turbulence Research, Proceedings of the Summer Program 1988. Paper no. N89-24555.Google Scholar
Joseph, P. & Parry, A. 2001 Rotor/wall boundary-layer interaction broadband noise in turbofan engines. In 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, Netherlands. AIAA.Google Scholar
Lynch, D. A., Blake, W. K. & Mueller, T. J. 2005a Turbulence correlation length-scale relationships for the prediction of aeroacoustic response. AIAA J. 43, 11871197.Google Scholar
Lynch, D. A., Blake, W. K. & Mueller, T. J. 2005b Turbulent flow downstream of a propeller. Part 1. Wake turbulence. AIAA J. 43, 11981210.Google Scholar
Lynch, D. A., Blake, W. K. & Mueller, T. J. 2005c Turbulent flow downstream of a propeller. Part 2. Ingested, propeller-modified turbulence. AIAA J. 43, 12111220.Google Scholar
Majumdar, S. & Peake, N. 1998 Noise generation by the interaction between ingested turbulence and a rotating fan. J. Fluid Mech. 359, 181216.Google Scholar
di Mare, L., Simpson, G. & Sayma, A. I.2006 Fan forced response due to ground vortex ingestion. In ASME. Turbo Expo: Power for Land, Sea, and Air, Volume 5: Marine; Microturbines and Small Turbomachinery; Oil and Gas Applications; Structures and Dynamics, Parts A and B, pp. 1123–1132. ASME.Google Scholar
Martinez, R. 1996 Asymptotic theory of broadband rotor thrust. Part II. Analysis of the right frequency shift of the maximum response. J. Appl. Mech. 63, 143148.Google Scholar
Martinez, R. 1997 Broadband sources of structure-borne noise for propulsors in ‘haystacked’ turbulence. J. Comput. Struct. 65 (3), 475490.Google Scholar
Martio, J., Sipilä, T., Sanchez-Caja, A., Saisto, I. & Siikonen, T. 2011 Evaluation of the propeller hull vortex using a RANS solver. In Second International Symposium on Marine Propulsors, Hamburg, Gemany.Google Scholar
Meyers, T., Forest, J. & Devenport, W. 2015 The wall-pressure spectrum of high-Reynolds-number turbulent boundary-layer flows over rough surfaces. J. Fluid Mech. 768, 261293.Google Scholar
Minniti, R. J., Blake, W. K. & Mueller, T. J. 2001a Inferring propeller inflow and radiation from near-field response. Part 1. Analytic development. AIAA J. 39 (6), 10301036.Google Scholar
Minniti, R. J., Blake, W. K. & Mueller, T. J. 2001b Inferring propeller inflow and radiation from near-field response. Part 2. Empirical application. AIAA J. 39 (6), 10371046.Google Scholar
Moiseev, N., Lakshminarayana, B. & Thompson, D. E. 1978 Noise due to interaction of boundary-layer turbulence with a compressor rotor. J. Aircraft 15, 5361.Google Scholar
Morton, M.2012 Rotor inflow noise caused by a boundary layer: inflow measurements and noise predictions. Master’s thesis, Virginia Tech.Google Scholar
Morton, M., Devenport, W., Alexander, W. N., Glegg, S. A. L. & Borgoltz, A. 2012 Rotor inflow noise caused by a boundary layer: inflow measurements and noise predictions. In 18th AIAA/CEAS Aeroacoustics Conference (33rd AIAA Aeroacoustics Conference), Colorado Springs, CO. AIAA.Google Scholar
Murphy, J. P. & MacManus, D. G. 2011 Inlet ground vortex aerodynamics under headwind conditions. J. Aerospace Sci. Technol. 15 (3), 207215.Google Scholar
Murray, H.2016 Turbulence and sound generated by a rotor operating near a wall. Master’s thesis, Virginia Tech. http://vtechworks.lib.vt.edu/handle/10919/71332.Google Scholar
Preisser, J. S., Brooks, T. F. & Martin, R. M. 1994 Recent studies of rotorcraft blade–vortex interaction noise. J. Aircraft 31 (5), 10091015.Google Scholar
Sato, R., Tasaki, R. & Nishiyama, S. 1986 Observation of flow on a horizontal flat plate above a working propeller and physics of propeller-hull vortex cavitation. In Proceedings of the International Symposium on Propeller and Cavitation, Wuxi, China, pp. 118125.Google Scholar
Sevik, M.1974 Sound radiation from a subsonic rotor subjected to turbulence. In Fluid Mechanics, Acoustics and Design of Turbomachinery, Pt. 2, NASA SP-304, pp. 493–512.Google Scholar
Sharpf, D. & Mueller, T. 1995 An experimental investigation of the sources of propeller noise due to the ingestion of turbulence at low speed. Exp. Fluids 18 (4), 277287.Google Scholar
Shin, H. W., Cheng, W. K., Greitzer, E. M. & Tan, C. S. 1986 Inlet vortex formation due to ambient vorticity intensification. AIAA J. 24 (4), 687689.Google Scholar
de Siervi, F., Viguier, H., Greitzer, E. & Tan, C. 1982 Mechanisms of inlet-vortex formation. J. Fluid Mech. 124, 173207.Google Scholar
Stephens, D. & Morris, C. 2009 Sound generation by a rotor interacting with a casing turbulent boundary layer. AIAA J. 47, 26982708.Google Scholar
Wisda, D., Alexander, W. N., Devenport, W. & Glegg, S. A. L. 2014 Boundary layer ingestion noise and turbulence scale analysis at high and low advance ratios. In 20th AIAA/CEAS Aeroacoustics Conference, Atlanta, GA. AIAA 2014-2608.Google Scholar
Wisda, D., Murray, H., Alexander, W. N., Nelson, M., Devenport, W. & Glegg, S. A. L. 2015 Flow distortion and noise produced by a thrusting rotor ingesting a planar turbulent boundary layer. In 21st AIAA/CEAS Aeroacoustics Conference, Dallas, TX.Google Scholar
Wojno, J., Mueller, T. & Blake, W. 2002a Turbulence ingestion noise. Part 2. Rotor aeroacoustic response to grid generated turbulence. AIAA J. 40, 2632.Google Scholar
Wojno, J., Mueller, T. & Blake, W. K. 2002b Turbulence ingestion noise. Part 1. Experimental characterization of grid-generated turbulence. AIAA J. 40, 1625.Google Scholar