Measuring Principle Coriolis Mass Flowmeters

Measuring Principle Coriolis

Coriolis forces Fc are generated in oscillating systems when a liquid or a gas moves away from or towards an axis of oscillation.

A Coriolis measuring system is of symmetrical design and consists of one or two measuring tubes, either straight or curved.

A driver sets the measuring tube (AB) into a uniform fundamental oscillation mode.

When the flow velocity v = 0 m/s / 0 ft/s, the Coriolis force Fc is also 0. At flowing conditions, i. e. flow velocity v > 0 m/s / 0 ft/s, the fluid particles in the product are accelerated between points AC and decelerated between points CB.

The Coriolis force Fc is generated by the inertia of the fluid particles accelerated between points AC and of those decelerated between points CB.

This force causes an extremely slight distortion of the measuring tube that is superimposed on the fundamental component and is directly proportional to the mass flowrate.

This distortion is picked up by special sensors. Since the oscillatory characteristics of the measuring tube are dependent on temperature, the temperature is measured continuously and the measured values corrected accordingly.