Thermal Gas Mass Flow Meter – Direct Measurement of Gas Mass Flow Rates

Principle
The flow meter's sensor consists of two thermal resistances (Pt100 RTD), one is gas mass flow speed sensor, short for T1; another is used to measure gas temperature,  short for T2. When the two sensors immerge the measured gas, sensor T1 are heated to a constant temperature more than temperature of T2.  The flowing gas will take away heat from T1, make temperature of T1 drop, in order to keep the constant temperature difference between T1 and T2, T1 must be heated continually, which will consumes energy.
     According to the Kim's law of thermal effect, there is a certain mathematical relationship among heating power: P,  temperature difference: Δ T (T1-T2) and gas mass flow: Q .
     This relationship as follow
      P/ΔT = K1 +  K2f (Q) ^ K3
K1, K2, K3 are constants related to the gas physical properties.
 
Application
1. Oxygen, Nitrogen, Hydrogen, Chlorine and fixed components of mixed gas
2. Blast furnace gas
3. Flue gas
4. Biogas, Chlorine in water treatment
5. Compressed air
6. Natural gas, LPG
7. Ventilation system of power plant
8. Ventilation or exhaust system in mines
 
Features 
1. Measure gas mass flow, not need temperature and pressure compensation.
2. Wide Turndown rate, flow velocity: 0.1 Nm/s to 100Nm/s.
3.No pressure drops
4. Anti-corrosion body material, applicable to corrosive gas
5. Insertion type sensor is convenient for installation and maintenance