Electromagnetic apparatus for measuring the flow velocity of an electrically conductive fluid and method of calibration thereof

Abstract

An electromagnetic apparatus for measuring the flow velocity of an electrically conductive fluid is placed in the fluid flow and has a pair of pipe portions, one pipe portion being placed within the other. Means is provided for producing a magnetic field in the fluid flow, this means being mounted between pipe portions. The pipe portions carry a number of electrodes positioned at right angles to both the direction of the fluid flow and the direction of the produced magnetic field and serving to sense the electric potential. Calibration of the apparatus is performed by passing the fluid flow through the internal pipe portion, the potential difference proportional to the fluid flow velocity being sensed by electrodes mounted on the internal pipe portion. The internal pipe portion makes it possible to calibrate the apparatus with small amount of fluid flow. In case the apparatus is employed to measure flow velocity in pipelines, the internal pipe portion of said apparatus can be made to extend through the wall of the pipeline, and this allows to check the apparatus in operation. To increase the intensity of the magnetic field, a magnetic core is inserted into the internal pipe portion. In this case, for the time of calibration this magnetic core is replaced by an equivalent magnetic core mounted outside the outer pipe portion.

Dependencies are inferred from the claim text.