Geometric decision of the floating magnet and the coil for airflow energy harvester based on push-pull diamagnetic levitation structure

In this paper, the levitation characteristics of the floating magnet in an airflow energy harvester based on diamagnetic levitation structure is studied by theoretical analysis and simulation calculation. According to the simulation with COMSOL Multiphysics, we obtained the relationship between the inductive voltage and the values of the notch radius, the floating magnet radius and the floating magnet thickness. At the same time, the coil parameters, including inner diameter, outer diameter, wire diameter and coil layer, were analyzed to study the influence of energy conversion factor (ECF) and energy conversion efficiency of the airflow energy harvester. Based on the analysis results, corresponding parameters are selected for experiment. And the results show that the peak voltage is 1.892 V, and the average power is 94.70 mW when the left and right nozzles’ gas flow rate is 3000 sccm. The simulation analysis provides a good reference for parameters selection of the floating magnet and the coil in the diamagnetic airflow energy harvester, which can increase the energy harvesting efficiency of the harvester.