There are many well documented flow meter technologies that are essentially trying to accomplish the same thing: measure fluid flow rate. Some of the technologies that are entrenched in the market, such as flow meters that utilize differential pressure as the measurement principle, are well understood by customers. Thermal mass flow meters however, such as the Magnetrol® Thermatel® TA2, are a rapidly growing technology that is continuously evolving.
Most flow meters inherently measure a flow rate at operating temperature and pressure, rather than the often desired mass flow rate at standard temperature and pressure (STP). Examples of flow rates at operating conditions are CFM or m3/h. The conversion to mass flow involves measuring operating temperature and pressure as well as knowing the STP conditions. This calculation can be accomplished outside of the flow meter or using a multivariable transmitter. When the term “mass flow meter” is discussed in the instrumentation world it is typically describing a Coriolis flow meter. Similar to Coriolis technology, thermal mass flow meters measure a flow rate at standard conditions (SCFM or Nm3/h) without the need for external measurements or additional calculations.