Wu Yutang, Wu Yunxin
School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China.
State Key Laboratory of High-Performance Complex Manufacturing, Central South University, Changsha 410083, China.
Sensors (Basel). 2020 Sep 7;20(18):5096. doi: 10.3390/s20185096.
The poor conversion efficiency and obvious lift-off effect of the electromagnetic acoustic transducer (EMAT) are commonly known to be problems for its practical application. For the purpose of enhancing the performance of EMATs, numerical simulations were performed in order to analyze the effect of various parameters. The results indicate that only the magnet-to-coil distance can effectively enhance the conversion efficiency and weaken the lift-off effect at the same time. When the magnet-to-coil distance is 2 mm, the lift-off effect will continue to be weakened as the magnet-to-coil distance increases, whereas the decrease of the lift-off effect is inconspicuous and the conversion efficiency starts to decline at this time. Therefore, to get the best performance of this specific EMAT, the suitable magnet-to-coil distance is 2 mm. The experiment effectively verifies the improvement of EMATs with a magnet-to-coil distance of 2 mm.
电磁超声换能器（EMAT）的转换效率低和明显的提离效应是其实际应用中众所周知的问题。为了提高EMAT的性能，进行了数值模拟以分析各种参数的影响。结果表明，只有磁体到线圈的距离能够同时有效提高转换效率并减弱提离效应。当磁体到线圈的距离为2mm时，随着磁体到线圈距离的增加，提离效应将继续减弱，而此时提离效应的减小并不明显，且转换效率开始下降。因此，为了使这种特定的EMAT获得最佳性能，合适的磁体到线圈距离为2mm。实验有效地验证了磁体到线圈距离为2mm时EMAT的性能提升。
