Electromagnetic flowmeter for insulating liquids

The conventional electromagnetic (EM) flowmeter is useable with electrically conductive fluids; there is no triboelectric noise, and a Ion, 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.