A hot-wire probe to simultaneously measure velocity vector and temperature fields
Abstract
A five-sensor probe capable of simultaneously measuring the 3-D velocity and temperature fields of a hot air flow has been constructed and tested. One pair of 2.5 micron diameter sensors is in an X-arrangement in the vertical direction and another pair is in the horizontal direction, forming a tetrahydron geometry. The fifth sensor, operated at very low overheat for temperature measurements, is placed in front of the velocity sensors. An optimal separation of temperature and velocity sensors, for a given overheat ratio, has been determined in order to minimize the thermal influence on the temperature sensor. The probe has been tested in a calibration rig capable of inducing variable velocity and temperature fields. Testing was performed in the range of 0.5-5 m/s and 20-100 deg. C. The solution uniqueness range of the probe's operational equations has been examined at room and elevated temperatures. It was found that the solutions were unique in the range of velocity ratios, V/U and W/U, up to 0.8, and that the uniqueness range was not affected by increasing temperature. The measured velocity and temperatures are in agreement with induced values, with high accuracy, over the whole range of variation.
- Publication:
-
APS Division of Fluid Dynamics Meeting Abstracts
- Pub Date:
- November 2003
- Bibcode:
- 2003APS..DFD.EF003V