A fully compensated hot/cold wire anemometer system for unsteady flow velocity and temperature measurements

Publisher Website
Google Scholar
Abstract
Constant-current anemometers operating as resistance thermometers are ideally suited for measurement of stream temperature fluctuations. In order to extend their limited frequency response due to the thermal inertia of the wire, open-loop compensation using a zero-pole network is often used. This method becomes unsatisfactory for unsteady flows with large velocity changes as the time constant of the wire changes significantly from instant to instant. An instantaneous velocity-dependent compensation method is described for use with a velocity-temperature probe. Once set, the compensator time constant matches the wire time constant at all times. Limits for good compensation are presented.