A new test stand for measuring wall shear stress


C. E. Tinney and Valdez, J. A., “A new test stand for measuring wall shear stress,” 2018 AIAA Fluid Dynamics Conference, AIAA Paper 2018-3085. Atlanta, Georgia, USA, 2018.


The design, construction and preliminary measurements of a new test stand for accurately assessing the shear stress acting at the fluid surface interface of wall bounded flows is discussed. This stand is based on control volume analysis whereby a fully developed turbulent velocity profile produces shear forces which equate to the pressure drop measured between fixed points in a constant area pipe. The calibration stand is designed to facilitate both subsonic and supersonic flow. Subsonic flow conditions are achieved by placing different diameter nozzles at the exhaust of the test section thereby permitting different free stream velocities and mass flow rates for a given ratio of the total pressure to static pressure in the pipe. The advantages of this facility is in its ability to produce a broad
range of Reynolds numbers (based on centerline velocity and pipe diameter) and elevated
pressures that are required to gauge the sensitivity of modern shear stress sensors.