A flow-velocity sensor probe includes a thermistor for generating heat which is placed in a fluid, and a waterproof resin and a metal piece for easily radiating the heat generated by the thermistor. The flow velocity of the fluid is measured continuously from a change of temperature in the thermistor,...http://www.google.ca/patents/US5373850?utm_source=gb-gplus-sharePatent US5373850 - Flow-velocity sensor probe
