Electromagnetic energy harvesting from vibrations induced by Kármán vortex street

A new electromagnetic energy harvester for harnessing energy from vibration induced by Kármán vortex street is proposed. It converts flow energy into electrical energy by fluid flow, vortex shedding from a bluff body and electromagnetic induction. An analytical design method for the energy harvester is developed. A prototype of the energy harvester is fabricated and tested. The prototype has a volume of 37.9 cm. Experimental results show that an output peak-to-peak voltage of nearly 20 mV in average is generated when the excitation pressure oscillates with an amplitude of 0.3 kPa and a frequency of about 62 Hz. By detecting the voltage drop across a matched load, the instantaneous power is determined as 1.77 μW under a pressure fluctuation frequency of 62 Hz and a pressure amplitude of 0.3 kPa in the Kármán vortex street.