The dynamic performance of micro-machined Coriolis flow meters
The performance of a prototype MEMS mass-flow meter developed by ISSYS was investigated using the Brunel University Virtual Coriolis Meter facility. The flow meter comprises a vacuum sealed vibrating flow tube and associated electronics which provide both the tube drive and processing of signals from the internal sensors. The selected device has typical (liquid) flow rates of order 0.1 mg/s and has potential applications in medicine (drug infusion) and automotive fuel injection technology. The simulation facility comprises finite element modelling of the motions of the vibrating tube with a 1-dimensional frictionless flow through it, thus allowing the generation of pseudo-data at points on the tube corresponding to the internal sensor locations. Signal processing algorithms then enable representation of an indicated meter flow-time history (output), in response to a prescribed flow input. Results have shown that the device is linear and that its sensitivity is uninfluenced by fluid density, but is very strongly dependent upon location of the internal sensors. The dynamic response time is given by the reciprocal of the drive frequency (typically 0.1 ms) for water flow, and the device step response shows noise due to signal components at the Coriolis frequency. The ramp response shows there is no significant noise induced.
Journal: TechConnect Briefs
Volume: 3, Technical Proceedings of the 2006 NSTI Nanotechnology Conference and Trade Show, Volume 3
Published: May 7, 2006
Pages: 336 - 339
Industry sector: Sensors, MEMS, Electronics
Topics: MEMS & NEMS Devices, Modeling & Applications