Measurements were made of the mean velocity profiles and wall pressure field upstream and downstream of the flow over both a backward-facing and forward-facing step. For each configuration the velocity profiles show that the effects of the separation-reattachment process persist more than 24 step heights downstream of the step. Extremely high values of the RMS wall pressure are measured near reattachment. These values are 5 and 10 times larger than on a smooth flat plate for the backward-facing step and the forward-facing step, respectively. The spectral density of the wall pressure fluctuations in the recirculation region is dominated by low frequency components. Downstream of reattachment there is a reduction in the low frequency content of the wall pressures and an increase in the high frequency components. At the farthest measured position downstream, the spectral density is still higher than that found on a smooth flat plate. These results show that the complex turbulent flow generated by a surface irregularity can significantly increase the localized wall pressure field and these increases persist far downstream of the irregularity. Consequently, a surface irregularity can be a major source of turbulence-induced vibrations and flow noise, as well as a cause of the inception of cavitation in marine applications.
Skip Nav Destination
Article navigation
July 1984
This article was originally published in
Journal of Vibration, Acoustics, Stress, and Reliability in Design
Research Papers
Effects of Surface Irregularity on Turbulent Boundary Layer Wall Pressure Fluctuations
T. M. Farabee,
T. M. Farabee
David W. Taylor Naval Ship Research and Development Center, Ship Acoustics Department, Bethesda, Maryland
Search for other works by this author on:
M. J. Casarella
M. J. Casarella
Catholic University of America, Department of Mechanical Engineering, Washington, D.C.; David W. Taylor Ship Research and Development Center, Ship Acoustics Department, Bethesda, Maryland
Search for other works by this author on:
T. M. Farabee
David W. Taylor Naval Ship Research and Development Center, Ship Acoustics Department, Bethesda, Maryland
M. J. Casarella
Catholic University of America, Department of Mechanical Engineering, Washington, D.C.; David W. Taylor Ship Research and Development Center, Ship Acoustics Department, Bethesda, Maryland
J. Vib., Acoust., Stress, and Reliab. Jul 1984, 106(3): 343-350 (8 pages)
Published Online: July 1, 1984
Article history
Received:
March 28, 1984
Online:
November 23, 2009
Citation
Farabee, T. M., and Casarella, M. J. (July 1, 1984). "Effects of Surface Irregularity on Turbulent Boundary Layer Wall Pressure Fluctuations." ASME. J. Vib., Acoust., Stress, and Reliab. July 1984; 106(3): 343–350. https://doi.org/10.1115/1.3269200
Download citation file:
Get Email Alerts
Related Articles
An Attempt to Scale the Vibrations of Water Pipes
J. Pressure Vessel Technol (November,2006)
Measurements of Fluctuating Wall Pressure for Separated/Reattached Boundary Layer Flows
J. Vib., Acoust., Stress, and Reliab (July,1986)
Vortex Dynamics and Low-Pressure Fluctuations in the Tip-Clearance Flow
J. Fluids Eng (August,2007)
Related Proceedings Papers
Related Chapters
Investigation of Reynolds Number Scale Effects on Propeller Tip Vortex Cavitation and Propeller-Induced Hull Pressure Fluctuations
Proceedings of the 10th International Symposium on Cavitation (CAV2018)
Cavitating Structures at Inception in Turbulent Shear Flow
Proceedings of the 10th International Symposium on Cavitation (CAV2018)
Antilock-Braking System Using Fuzzy Logic
International Conference on Mechanical and Electrical Technology, 3rd, (ICMET-China 2011), Volumes 1–3