A &#;sonic nozzle&#; (also known as &#;Critical Flow Venturi&#; or &#;Critical Flow Nozzle&#;) is a flow meter that can be used as a calibration standard for gas flow meters or any flow measurement device. By design, sonic nozzles are a constant volumetric flow meter.
Click here to get more.
The nozzles are designed and manufactured to the ISO standard and as such the gas is accelerated along the Bell Mouth converging section and then is expanded in a conical diverging section, which is designed for pressure recovery.
tnma contains other products and information you need, so please check it out.
In the throat, or minimum area point of the Sonic Nozzle, the gas velocity becomes equal to the speed of sound. At this point, gas velocity and density are maximized, and the mass flow rate is now a function of the inlet pressure, inlet temperature, and the type of gas.
The gas meters are tested at three or more measuring points. A magazine made of three sonic nozzles is used as a flow sensor. The nozzle magazine can be exchanged with just a few hand movements so that up to five different as meter types can be calibrated on one test bench. Optionally, a nozzle drum with nine combinable nozzles can be used. This allows the generation of up to 512 different flow points. This means that all five gas meter types G1.6&#;G10 can be tested without nozzle change.
If you want to learn more, please visit our website Bell-Prover Gas Meter Test Bench.