Measuring flow velocity at elevated temperature with a hot wire anemometer calibrated in cold flow

Correction factors enable a hot wire anemometer calibrated at room temperature to be utilised at elevated temperature. This short paper reviews the equations on which those correction factors are based. The standard methods of correction, which work only over moderate temperature changes of a few degrees in the ambient, have been investigated over a greater temperature range. Modified correction factors are effective over a velocity range of 0–14 m/s and temperature range of 300–500 K. The modified method of correction has been developed during research into the warm up of automotive catalysts and this has prescribed the range of velocity and temperature considered