July 31, 2010 — Sierra Instruments introduced a cryogenic version of their Innova-Mass multivariable mass vortex flow meter. This application has been historically serviced by the turbine flow meter, however given that the multivariable mass vortex meter has no moving parts to wear out or be serviced, the benefit of the instrument is a more reliable, stable reading and an increased service life.The new Innova-Mass cryogenic version has undergone extensive testing and field validation over the last several years proving that the meter is preferred versus traditional turbine meters for measuring mass flow rates of cryogenic fluids down to -328°F (-200°C).
Using a special cryogenic temperature RTD, mass calculations are done with the latest density equations of state for liquid Oxygen, Nitrogen, Argon, and CO2. The Innova-Mass Model 240 and Model 241 measure five process variables (mass flow, volumetric flow, temperature, pressure and density) through one process connection. Since everything is calibrated together, system accuracy is very high. Because mass flow is directly measured, the Reynolds number can be dynamically calculated and the flow profile effects in large pipes calculated in real time.
This allows Sierra’s unique insertion Model 241 to make reliable measurements in large pipes (up to 72 inches) where using an in-line meter would be cost prohibitive.The Innova-Mass is loop-powered, with power in, a programmable analog output and a HART or MODBUS signal riding on the same two wires.
