Answer / atul $onawane

electromagnetic flow meter works on the principle of fadays
law of induction. in this voltage induced in the conductor is
proportional to the velocity of fluid(conducting). only
conducting fluids and gases are used .

Answer / rajesh l parmar

Electromagnetic flow meter works on a principal of
faraday’s law or electromagnetic induction which states
that when a current carrying coinductor moves through a
stationary traverse magnetic field, then e.m.f. is induced
between the ends of the conductor and this e.m.f. is
proportional to relative velocity between conductor and
magnetic field

E = BLV where

B = magnetic induction

L = length of a conductor

V = velocity of the conductor relative to the magnetic
field

It consists of a flow tube inside a pipe which carries a
fluid flow. So when the fluid is passed through the flow
tube, it is visualized as a current carrying conductor
having a length equal to inside diameter of the flow tube.

Now the gas, steam and oils are having low electrical
conductance. So no E.M.F. can be generated in such case. So
electromagnetic flow meters can not be used for metering
gas, oil and steam.

In general electromagnetic flow meters can only be used to
measure the flow of fluid which are sufficient conductive
to generate e.m.f.

Answer / rajesh l parmar

Electromagnetic flow meter works on a principal of
faraday’s law or electromagnetic induction which states
that when a current carrying coinductor moves through a
stationary traverse magnetic field, then e.m.f. is induced
between the ends of the conductor and this e.m.f. is
proportional to relative velocity between conductor and
magnetic field

E = BLV where

B = magnetic induction

L = length of a conductor

V = velocity of the conductor relative to the magnetic
field

It consists of a flow tube inside a pipe which carries a
fluid flow. So when the fluid is passed through the flow
tube, it is visualized as a current carrying conductor
having a length equal to inside diameter of the flow tube.

Now the gas, steam and oils are having low electrical
conductance. So no E.M.F. can be generated in such case. So
electromagnetic flow meters can not be used for metering
gas, oil and steam.

In general electromagnetic flow meters can only be used to
measure the flow of fluid which are sufficient conductive
to generate e.m.f.

Answer / m n gopinath

electromagnetic meters are generally used with conductive
liquids having conductivity greater than 50 microsiemens/cm.

DM Water, gases,steams and hydrocarbons are non conductive,
hence cannot be used.

..however it can be used in acid or alkali services

Why is a vacuum breaker used on shell and tube heat exchangers that are utilizing steam as the heating utility?

0 Answers  

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hai....i am chandrika. if anybody having test questions for HAL,HPCL,ONGC,IOL...PLS SEND THE QUES WITH SOLVED ANSWERS TO ME TO MY MAIL ID chandrismiles@yahoo.co.uk

0 Answers   HAL,

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what is difference between urea and NPK fertiliser?

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Are there any alternatives to scraping a shell and tube if a capacity increase will make the pressure drop across the exchanger too large?

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viscosty of crude use for petroliun?

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Explain the functioning of a three-way catalytic converter.

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how interstage pressure of multistage compressor is calculated?

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