An Alternating Field Induction Flow Meter of High Sensitivity

An electromotive force is induced in a fluid moving in a pipe at right angles to a magnetic field. This effect can be used to measure magnetic fields by maintaining a known flow or to measure the discharge of a fluid through a pipe by maintaining a known magnetic field. The flow of poor electrolytic conductors like tap water can be measured as well as the flow of a liquid metal like, for instance, mercury. A modification of the apparatus for the purpose of measuring the velocity distribution and fluctuations of the instantaneous velocity in large channels comprising a minute magnet with attached electrodes is described.