Title :
Electromagnetic flowmeter for insulating liquids
Author :
Cushing, Vincent
fDate :
6/24/1905 12:00:00 AM
Abstract :
The conventional electromagnetic (EM) flowmeter is useable with electrically conductive fluids, there is no triboelectric noise, and a low frequency square wave induction is used. Turbulently flowing nonconductive fluids have substantial triboelectric noise, with spectral density experimentally measured to be about f -2.6. High frequency induction remedies the triboelectric noise problem, but the rapidly repetitive dB/dt introduces excessive zero-point offset. Here we describe an electromagnet and signal processor that allow high frequency induction and discriminate against the offset - such that the EM flowmeter can be used with any fluid, whether conductive or insulating.
Keywords :
eddy currents; electromagnetic devices; electromagnetic induction; equivalent circuits; flowmeters; random noise; signal sampling; Lorentz transformation; calibration; decaying offset voltage; eddy currents; electromagnetic flowmeter; equivalent circuit; excessive zero-point offset; high frequency induction; inherent shunting capacitance; insulating liquids; signal processor; time series; transducer design; triboelectric noise; true flow voltage; Density measurement; Dielectric liquids; Electromagnetic induction; Electromagnetic interference; Electromagnetic measurements; Electromagnetic scattering; Frequency; Insulation; Low-frequency noise; Noise measurement;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 2002. IMTC/2002. Proceedings of the 19th IEEE
Print_ISBN :
0-7803-7218-2
DOI :
10.1109/IMTC.2002.1006823
