Effect of pulsating flow on Coriolis mass flowmeters

The Effect of Flow Pulsations on Coriolis Mass Flow Meters

“…The foregoing conclusions regarding the behaviour of a Coriolis meter in a pulsatile flow can be compared to the experimental results reported by Vetter & Notzon (1994). Unfortunately, there is no mention in their paper of the method which is used to determine the phase difference in their test meter, nor is there any report of the characteristics of the raw detector signals.…”

“…There is no indication in the work of Vetter & Notzon (1994) that they were aware of the possibility of a resonance being excited by a fluid pulsation at double the frequency, and it must be noted that there is no indication on their figure 2 of such an effect at 155 Hz, where it might have been expected. It is not clear whether this is due to geometric differences between a straight tube meter and a U-tube meter, or to coarse spacing of excitation frequencies.…”

“…In their paper, Vetter & Notzon (1994) report the determination of the characteristic resonant frequencies of their test meter by passing a pulsatile flow through the meter with the feedback and drive to the meter disconnected. Because the fluid forces are distributed along the meter, it is not immediately obvious that a pulsatile flow at a particular frequency will excite motion of the meter at that frequency.…”

“…Only one report of an investigation into the influence of flow pulsations on meter accuracy has been found. Vetter & Notzon (1994) tested two sizes of U-tube type Coriolis meters and reported large meter errors for particular pulsation frequencies. The tests included both single-frequency, sinusoidal, flow pulsations and pulsations resulting both from piston pumps with fast acting valves and from gear pumps.…”

The Simulation of Coriolis Meter Response to Pulsating Flow Using a General Purpose F.E. Code

“…Vetter and Notzon (1994) reported the results of experiments involving two di!erent U-tube meters subjected to pulsations from a piston pulsator and from a gear pump. They reported irregular meter output signals with pulsations at the drive frequency and large meter errors with pulsations at the Coriolis frequency.…”