On temperature compensation in hot-wire anemometry

Abstract

The temperature sensitivity of a constant temperature, hot-wire anemometer has been experimentally investigated over a large range of ambient temperatures (22-98 degrees C) and for a low range of velocities (0.35-9 m s-1). From the large number of methods proposed in the literature for compensating the velocity reading of a hot-wire anemometer for temperature fluctuations in the flow, five different analytic approaches have been applied to the experiment data. Limitations and errors using the various methods are systematically examined. The most consistent compensation has been obtained using the relationship proposed by D.C. Collis and M.J. Williams (1959) in which fluid properties are evaluated at the mean film temperature.