A Piezoelectric Energy Harvester Based on

Pressure Fluctuations in Kármán Vortex Street

Dung-An Wang, Huy-Tuan Pham, Chia-Wei Chao, Jerry M.

Chen

National Chung Hsing UniversityTaichung, Taiwan

May 13, 2011

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National Chung Hsing University

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National Chung Hsing University

The KarmaThe KarmaFeng SuiFeng Sui

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Components of ancient feng shui

Healthy homes Sustainability Environment

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Energy harvesting from water flow

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Design

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Fabrication

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Experiment

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Experimental setupExperimental setup

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Result

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Result

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Result

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DiscussionDiscussion The output power of the device is relatively The output power of the device is relatively

low. low. An open circuit output voltage of 0.12 Vpp An open circuit output voltage of 0.12 Vpp

in average and an instantaneous output in average and an instantaneous output power of 0.7 nW for the pressure oscillates power of 0.7 nW for the pressure oscillates with an amplitude of ~0.3 kPa and a with an amplitude of ~0.3 kPa and a frequency of ~52 Hz. frequency of ~52 Hz.

Dimensions and structure of the device can Dimensions and structure of the device can be optimized to increase output power.be optimized to increase output power.

A piezoelectric material with higher A piezoelectric material with higher piezoelectric constants can be adopted. piezoelectric constants can be adopted.

Operate at the resonance frequency. Operate at the resonance frequency.

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DiscussionDiscussion The resonance frequency of the The resonance frequency of the

energy harvesting device can be energy harvesting device can be tailored to the shedding frequency of tailored to the shedding frequency of the Kármán vortex street in order to the Kármán vortex street in order to increase the output powerincrease the output power

For random and broadband ambient For random and broadband ambient flow sources, a structure with flow sources, a structure with multiple resonant frequencies may multiple resonant frequencies may also be considered, an array of the also be considered, an array of the device.device.

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Thank for your attention !