A thermal mass flow sensor uses the thermal properties of liquids to measure their mass flow rate. To this end, as can be seen in the figure, heat is introduced into the streaming liquid by a heater, and the (temperature) sensor measures how much heat is absorbed by the liquid. In these thermal mass flow meters for liquids, the heater as well as the sensor are built around a stainless-steel main flow channel tube with no moving parts or obstructions inside the tube. Read more
