A Coriolis flow meter can have either twin measuring tubes or a single measuring tube. The meter uses a drive coil to vibrates the tube(s), and pickoffs at each end measure the vibrations.
With zero flow, the vibrations are similar. But with flow, the tube(s) will reflect the Coriolis effect and show a time difference between the pickoffs. This difference is directly proportional to the mass flow rate. Also, when you have a density change, it affects the resonance. Higher density creates a lower resonance, and low density a high resonance.
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