Mathematical Model of Hot Wire Anemometer

This is a MathCad document that shows how the voltage output of a standard hot film anemometer is related the the flow velocity. It uses empirical relations for a cylinder in cross flow to predict the heat transfer.

This model compares well with experiments (15%), considering the manufacturing variations and the fact that a real hot film anemometer has a parabolic temperature distribution with the hottest part being in the center and a significant part of the heat being conducted into the support prongs.