A miniaturized gas flow energy harvester using diamagnetically stabilized levitation

In this paper, a miniaturized energy harvester is presented to scavenge gas flow energy. A magnet rotor with three teeth evenly distributed on the edge was introduced into the energy harvester, and it is frictionlessly levitated between two highly oriented pyrolytic graphite (HOPG) sheets. The energy harvester is designed to operate at a single stable equilibrium, so as to improve the stability of the rotor. The optimal incident angle of the gas flow was determined to be 83°. On the basis of the optimal angle, two different configurations of the energy harvester were proposed. Configuration A includes one nozzle, while Configuration B has two centrosymmetric nozzles. The maximum flow rate that enables Configurations A to work stably is limited, which can be increased by thickening the magnet rotor. The maximum voltage of configuration A was 0.28 V at a flow rate of 1500 sccm for the 4.5 mm thick rotor. Configuration B can run stably at any flow rate bigger than 250 sccm and the induced voltage increases with the driving flow rate. At the flow rate of 3000 sccm, the energy harvester of Configuration B can generate a maximum voltage of 3 V and light up tens of light-emitting-diodes (LEDs).