Thermal Mass Flow Meters

Thermal mass flow meters measure the mass flow rate of gases by monitoring how much heat is carried away from a heated sensor by the moving gas stream. They are widely used in both industrial settings—such as process control, emissions monitoring, and natural gas measurement—and in laboratory environments where precise gas delivery and monitoring are needed. Thermal mass meters are available in two main configurations: inline, where the sensor is built into the flow body for high accuracy in dedicated lines, and insertion, where a probe is inserted into larger ducts or pipes to measure flow at a representative point. Because they directly measure mass flow without the need for pressure or temperature compensation, thermal mass flow meters are convenient and reliable, though their performance can be influenced by gas composition and cleanliness.