Re: [Phys-l] Electromagnetic flow meter ?

[Brian Whatcott <betwys1@sbcglobal.net>]

At 06:46 AM 12/15/2008, Roberto Carabajal Perez, you wrote:
> Hello:
>
> We are trying to develop a lab experience building an 
> electromagnetic liquid flow meter 'magmeter'. We know that the 
> operation of a magnetic flowmeter is based upon Faraday's Law, which 
> states that the voltage induced across any conductor as it moves at 
> right angles through a magnetic field is proportional to the 
> velocity of that conductor.
>
> The liquid is salted water flowing at 1 m/s speed.
> As a tube, there is an hypodermic syringe (1.25 cm diameter), with 
> two conductive sensors in oposite sides.
> The magnetic field is provided by a 300 turns coil reeled on a TV 
> flyback ferrite nucleus, with a trasversal area of 1.5 cm2.
> The driving current is 2 A alternate current (50 Hertz).
> In the ferrite nucleus, there is a 1.25 cm gap, wide enough to hold 
> the tube (hypodermic syringe) inside it.
>
> We expected an induced voltage, suitable to be observed in an 
> osciloscope, but we can´t measure any useful signal.
> Has somebody carried out a similar experience? . Any suggestion?
>
> My best regards.
> Roberto

It would be interesting to see the experimental details, with a 
diagram of some kind.
I am imagining a salt solution flowing out of a syringe on whose 
interior is a pair of
 electrodes, and with pole pieces set perpendicular to those electrodes.
Is this anything like your arrangement?



Brian Whatcott    Altus OK    Eureka!