TY - JOUR
T1 - Multifunctional cantilevers as working elements in solid-state cooling devices
AU - Bradeško, Andraž
AU - Fulanović, Lovro
AU - Vrabelj, Marko
AU - Matavž, Aleksander
AU - Otoničar, Mojca
AU - Koruza, Jurij
AU - Malič, Barbara
AU - Rojac, Tadej
N1 - Funding Information:
Funding: The authors thank the Slovenian Research Agency for financial support in the frame of the doctoral project of Andraž Bradeško, projects J2-7526, PR-08298 (contract number BI-DE/18-19-007), L2-8180, and program P2-0105.
Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/3
Y1 - 2021/3
N2 - Despite the challenges of practical implementation, electrocaloric (EC) cooling remains a promising technology because of its good scalability and high efficiency. Here, we investigate the feasibility of an EC cooling device that couples the EC and electromechanical (EM) responses of a highly functionally, efficient, lead magnesium niobate ceramic material. We fabricated multifunctional cantilevers from this material and characterized their electrical, EM and EC properties. Two active cantilevers were stacked in a cascade structure, forming a proof-of-concept device, which was then analyzed in detail. The cooling effect was lower than the EC effect of the material itself, mainly due to the poor solid-to-solid heat transfer. However, we show that the use of ethylene glycol in the thermal contact area can significantly reduce the contact resistance, thereby improving the heat transfer. Although this solution is most likely impractical from the design point of view, the results clearly show that in this and similar cooling devices, a non-destructive, surface-modification method, with the same effectiveness as that of ethylene glycol, will have to be developed to reduce the thermal contact resistance. We hope this study will motivate the further development of multifunctional cooling devices.
AB - Despite the challenges of practical implementation, electrocaloric (EC) cooling remains a promising technology because of its good scalability and high efficiency. Here, we investigate the feasibility of an EC cooling device that couples the EC and electromechanical (EM) responses of a highly functionally, efficient, lead magnesium niobate ceramic material. We fabricated multifunctional cantilevers from this material and characterized their electrical, EM and EC properties. Two active cantilevers were stacked in a cascade structure, forming a proof-of-concept device, which was then analyzed in detail. The cooling effect was lower than the EC effect of the material itself, mainly due to the poor solid-to-solid heat transfer. However, we show that the use of ethylene glycol in the thermal contact area can significantly reduce the contact resistance, thereby improving the heat transfer. Although this solution is most likely impractical from the design point of view, the results clearly show that in this and similar cooling devices, a non-destructive, surface-modification method, with the same effectiveness as that of ethylene glycol, will have to be developed to reduce the thermal contact resistance. We hope this study will motivate the further development of multifunctional cooling devices.
KW - Cooling
KW - Electrocaloric response
KW - Electromechanical response
KW - Multifunctional materials
UR - http://www.scopus.com/inward/record.url?scp=85102917346&partnerID=8YFLogxK
U2 - 10.3390/act10030058
DO - 10.3390/act10030058
M3 - Article
AN - SCOPUS:85102917346
SN - 2076-0825
VL - 10
SP - 1
EP - 13
JO - Actuators
JF - Actuators
IS - 3
M1 - 58
ER -