A numerical study on Faraday-type electromagnetic flowmeter in liquid metal system, (II) - Analysis of end effect due to saddle-shaped small-sized magnets with FALCON code

In the design of the electromagnetic flowmeter (EMF) in the main cooling lo op of the Japanese Prototype Fast Breeder Reactor "MONJU", large-sized flat permanent magnet was adopted in order to make the end effect of the magnet as small as possible. For an EMF of a future large LMFBR, it is difficult to adopt such a large-sized magnet because of problems of a large space req uirement and a tolerance against earthquake. Therefore, it is necessary to develop a novel EMF with small-sized magnets. It has been feared that the d ecrease of magnetic field and the end effect make the EMF's performance wor se, but we have no detailed information about the end effect due to such sm all-sized magnets. By using the three-dimensional steady-state electromagne tic analysis code FALCON, we have studied numerically on the end effect of an EMF with saddle-shaped permanent magnets, the size of which is smaller t han the pipe diameter. Consequently, it has been clarified that the perform ance of an EMF can be improved by utilizing the effect of the downstream en d of magnets and by combining the inclined-electrodes and the effect of cir cumferential ends of magnets.