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Vibration induced refrigeration using ferroelectric materials.

ABSTRACT: This article aims to propose a cantilever based cooling device employing non-axis symmetric placement of bulk ferroelectric patches. Ambient mechanical vibrations produce large stresses in cantilevers resulting in elastocaloric effect associated with ferroelectrics. Further, design allows cascading of several cantilevers to achieve large cooling response. A finite element analysis of the system was performed using material properties of bulk 0.50Ba(Zr_0.2Ti_0.8)O₃-0.50(Ba_0.7Ca_0.3)TiO₃. An individual element could produce a peak elastocaloric effect of 0.02?K (324?K); whereas the proposed system could achieve a temperature drop of 0.2?K within 50?seconds (10 elements, 1.5?Hz). Furthermore, net cooling can be further improved about ~2?K (using 10 cantilevers) for a starting temperature of 358?K. This study shows that elastocaloric effect in ferroelectric materials is capable of converting waste mechanical vibration into refrigeration effect which is not reported so far.

SUBMITTER: Kumar A

PROVIDER: S-EPMC6408585 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Vibration induced refrigeration using ferroelectric materials.

Kumar Anuruddh A Chauhan Aditya A Patel Satyanarayan S Novak Nikola N Kumar Rajeev R Vaish Rahul R

Scientific reports 20190308 1

This article aims to propose a cantilever based cooling device employing non-axis symmetric placement of bulk ferroelectric patches. Ambient mechanical vibrations produce large stresses in cantilevers resulting in elastocaloric effect associated with ferroelectrics. Further, design allows cascading of several cantilevers to achieve large cooling response. A finite element analysis of the system was performed using material properties of bulk 0.50Ba(Zr0.2Ti0.8)O3- ...[more]

PMID: 30850629

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