Quantitech has launched an interesting in-pipe gas flow monitoring technology that also measures gas composition and is unaffected by temperature, density, viscosity or pressure.
Sales director Dominic Duggan explains that when the speed of sound is measured along a path in both directions simultaneously, the difference is proportional to gas velocity.
Measurements at 100 mbar are feasible, he says, and flow rates between 0.01 l/min and 200 l/min can be handled in pipes up to 200mm in diameter. Running from a 24V dc supply, the meters respond rapidly and output data in variety of formats.
For single gases, any change in the speed of sound measurement indicate that the purity of the gas has changed. For mix of two gases, speed of sound is then a combination of the two main gas components.
"So there is a simple calculation to derive the proportion of each component," states Duggan.
"For example, the speed of sound for pure CO2 is 259 m/sec, and for Methane it is 430 m/sec. So, if the speed of sound measurement is 401 m/sec, the gas composition is 83% Methane and 17% carbon dioxide."
