| Abstract [eng] |
Technological advantages are the main cause of popularity of electromagnetic fluid flow converters with cylindrical channel. But electrode signal of electromagnetic fluid flow converters with rectangular channel sensors has the significantly lower dependence on a velocity profile in the cross-section of the channel. Sensitivity of electromagnetic fluid flow converters with rectangular channel is higher. It is showed, that using the same magnetic field excitation coils with the same current, the electromagnetic flow converters with rectangular channel has more than 1.5 times sensitivity, than the electromagnetic flow transducers with cylindrical channel. The sensitivity increases, when ratio between high and base of channel rectangular cross-section decreases. There are better to use rectangular magnetic core in the electromagnetic flow converters with rectangular channel, directing the longer side of core cross-section perpendicularly to channel axis. The magnetic material, needed for core manufacturing, can be diminished till two times comparing with cylindrical core in this case, when the magnetomotive force is the same. By simulation, using finite element method, the magnetic cores of rectangular and circular shapes were compared in the electromagnetic flow converters with perpendicular channel. In the flow transducers with rectangular core shape the sensitivity dependence on velocity profile is significantly lower. Using core of perpendicular shape with longer side 2.33 times more than shorter side in the range of average velocity 0-8m/s the variation of sensitivity is not exceeded of limits [-0.28%, 0.31%]. Using core of perpendicular shape with longer side 1.66 times more than shorter side in the range of average velocity 2-8m/s the variation of sensitivity is not exceeded of limits ±0.03%. By widening the electrodes, the variation of sensitivity can be diminished in the range of average velocity 0-8m/s. |
