The dynamic response of Coriolis flowmeters

Abstract

The paper describes the results of an investigation into the dynamic response of Coriolis mass flow meters. Attention is directed to the response of the flow tube and implications arising directly from this response. A three pronged approach was adopted, beginning with a theoretically analysis of a simple straight tube meter, proceeding to a finite element simulation of the same meter and then to simulations of a number of different commercially available meters (different geometries) and finishing with experimental tests on a total of eight meters covering five different geometries. At an early stage in the work it became clear that the dynamic response time is determined by the resonant frequency of the mode in which a meter is driven and that it is not possible to obtain independent flow rate data more frequently than once per cycle of the meter drive. The experimental work involved both 'step' changes which occurred over more than one drive cycle. The response to low frequency (compared to the drive frequency) pulsations in the flow rate was also investigated. (15 pages)