Numerical and experimental analyses on optimal air gaps of an electromagnet-type stirrer

An electromagnetic stirrer is a device that uses electromagnets to rotate a stir bar. In this study, its performance with respect to its magnetic circuit was numerically and experimentally analyzed. Two-dimensional finite element analysis was used to model and analyze its magnetic circuit with regard to two major parameters: yoke air gap and stir bar height. The deorbiting time was defined in order to quantify its performance and was used in the experiments. The numerical and experimental results consistently showed that an optimal air gap exists and should be determined in connection with the height of the stir bar.