Abstract
A method of calibrating surface mounted thin film gauges to measure aerodynamic wall shear stress in laminar flow is presented. Hot wire measurements from the boundary-layer on a flat plate are used to find the first calibration constant and the shear stress predictions for a cylinder in cross flow are used to find the second. The cylindrical shape incorporates a favourable pressure gradient into the calibration method. Good agreement has been found between aerodynamic experimental results for the two shapes which suggests that a unique calibration exists. All experiments used Dantec 55R47 gauges operated at an overheat of 383 K above a reference temperature of 293 K. A new semi-empirical theory is used for the purpose of calibration. Input of experimental data enables the calculation of the equation parameters so that the new theory may be applied to a gauge mounted on a variety of surface profiles. Finally, calibrated gauges are used to measure the wall shear stress in laminar flow at four chordwise positions on the suction surface of a turbine blade in a two dimensional cascade.
| Original language | English |
|---|---|
| Pages (from-to) | 8 |
| Number of pages | 8 |
| Journal | American Society of Mechanical Engineers (Paper) |
| Publication status | Published - 1995 |
| Event | Proceedings of the International Gas Turbine and Aeroengine Congress and Exposition - Houston, TX, USA Duration: 5 Jun 1995 → 8 Jun 1995 |