Classification and application of flow meters Posted by : admin / Posted on : Jul 13， 2019

  Meters that measure fluid flow are collectively referred to as flow meters or flow meters. The flow meter is one of the most important instruments in industrial measurement. With the development of industrial production, the accuracy and range of flow measurement requirements are getting higher and higher, and the flow measurement technology is changing with each passing day. Various types of flow meters have been introduced to suit various applications. More than 100 flow meters have been put into use. From different perspectives, flow meters have different classification methods.
  There are two commonly used classification methods: one is to classify according to the measurement principle adopted by the flowmeter; the other is to classify according to the structural principle of the flowmeter.
 First, according to the principle of measurement
   1. Mechanics: Instruments belonging to such principles have differential pressure and rotor type using Bernoulli's theorem; impulse type and movable tube type using momentum theorem; direct mass type using Newton's second law; using fluid momentum The target type of the principle; the turbine type using the angular momentum theorem; the vortex type using the principle of fluid oscillation, the vortex type; the pitot tube type using the total static pressure difference, and the volumetric type, the enthalpy, the trough type and the like.
   2, electrical principles: instruments used in such principles are electromagnetic, differential capacitive, inductive, strain resistance and so on.
   3. Acoustic principle: Ultrasonic and acoustic (shock wave) are used to measure the flow using the acoustic principle.
   4, the principle of thermal: the use of thermal principles to measure the flow of the heat, direct calorimetry, indirect calorimetry and so on.
   5, optical principle: laser, photoelectric, etc. are instruments of this type.
   6, the original physical principles: nuclear magnetic resonance, nuclear radiation, etc. are instruments of this type.
   7, other principles: the principle of marking (trace principle, NMR principle), related principles.
flow meter