The Coriolis principle explains how a moving mass affects a body within a rotating frame of reference. As the mass moves, it applies an apparent force—known as the Coriolis force—on the motion of the body, resulting in its deformation. Notably, this force doesn’t act directly on the body but influences its movement. This principle forms the basis of Coriolis flow meters.
A Coriolis flow meter operates using two parallel tubes that are set into vibration by a magnetic driver. Sensors positioned at the inlet and outlet of these tubes monitor their oscillations. When there is no flow, the oscillations remain perfectly synchronized (in phase) since no mass flow is present to disturb them. However, as a fluid or gas passes through, Coriolis forces come into play. These forces induce a twisting motion in the tubes, with the degree of twist being directly proportional to the mass flow rate of the medium.
This twisting creates a phase shift between the inlet and outlet oscillations, which is detected by the sensors. The magnitude of this phase shift allows precise measurement of the mass flow rate. Additionally, the tubes vibrate at a natural resonant frequency influenced by the density of the medium inside. By analyzing these frequency changes, the system determines the fluid’s density. Combining mass flow rate and density enables calculation of the volume flow rate.
Thus, Coriolis flow meters provide accurate, simultaneous measurements of mass flow rate, density, and temperature for any fluid or gas moving through a pipeline.
