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Evaluation of the time dependent surface shear stress in turbulent flowsThe time dependent surface shear stress has been evaluated using surface heat transfer measurements. For fully developed turbulent pipe and open channel water flows, and incompressible and compressible turbulent boundary layer air flows the measurements indicate the absolute magnitude of the surface shear stress fluctuations will be greater than two times the mean values. The root-mean-square shear stress fluctuations were of the order of 0.2 to 0.4 times the mean surface shear values. Due to these large surface shear stress fluctuations and the nonlinear relation between heat transfer and shear stress, a special technique has been developed to evaluate the measurements. It was found that the non-linear averaging errors for a hot film-surface shear stress gauge in a fully developed pipe flow was of the order of 10 percent at low velocities. A hot wire-surface shear stress gauge was employed for measurements of turbulent boundary layers in air.
Document ID
19800034448
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Sandborn, V. A.
(Colorado State University Fort Collins, Colo., United States)
Date Acquired
August 10, 2013
Publication Date
December 1, 1979
Subject Category
Fluid Mechanics And Heat Transfer
Report/Patent Number
ASME PAPER 79-WA/FE-17
Meeting Information
Meeting: Winter Annual Meeting
Location: New York, NY
Start Date: December 2, 1979
End Date: December 7, 1979
Sponsors: American Society of Mechanical Engineers
Accession Number
80A18618
Funding Number(s)
CONTRACT_GRANT: NSF ENG-76-05-896
CONTRACT_GRANT: USDA-16-477-CA
CONTRACT_GRANT: NCA2-OR-165-604
Distribution Limits
Public
Copyright
Other

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