A system for measuring the velocity of a fluid can comprise a temperature sensor,
for measuring the ambient temperature of the fluid, an RTD placed in the flow path
of a fluid, the RTD being included as part of a Wheatstone bridge circuit, a digital
potentiometer, the digital potentiometer also being included as part of a Wheatstone
bridge circuit, and a controller coupled to the temperature sensor, the RTD and
the digital potentiometer. In the system, the controller adjusts the digital potentiometer
in response to an ambient fluid temperature signal from the temperature sensor
such that the temperature of the RTD remains at a constant differential temperature
above the ambient fluid temperature.
