This flow meter consists of a thin platinum wire, electrically heated to constant
temperature and centrally located in a tube As gas passes through the meter , and centrally located in a tube. As gas passes through the meter
the wire cools off, requiring extra electrical energy to maintain its temperature.
The extra electrical energy is a measure of gas flow. It is insensitive to the
direction of flow, the flow direction can be determined from the wire that cools
first. A disadvantage of this type of meter is its sensitivity to gas composition and
gas temperature