Surface shear stress measurement system for boundary layer flow over a salt playa

Abstract

A novel method for measuring shear stress via a floating surface element beneath a turbulent boundary layer has been tested and implemented. The final design is used for measuring the surface shear stress in the boundary layer that forms over the salt playa of western Utah. Wind tunnel model studies were conducted to establish the characteristics of two competing sub-designs, and to determine their sensitivities and potential error sources. The wind tunnel based experiments included independent comparisons with the results of wall velocity gradient based measurements using hot-wire data. Overall, the results show that a floating element on a pool of liquid, here water, provides a more accura..