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arXiv · 2303.15292

A comprehensive thermodynamic model for temperature change in i-caloric effects

A. M. G. Carvalho·W. Imamura
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Abstract

Solid-state cooling based on i-caloric effects may be an alternative to conventional vapor-compression refrigeration systems. The adiabatic temperature change ($\Delta T_{S}$) is one of the parameters that characterize the i-caloric effects, therefore it is important to obtain the correct $\Delta T_{S}$ values and, whenever possible, to correlate this parameter with thermodynamic and microscopic quantities. In this work, we propose a comprehensive thermodynamic model that allows us to determine the adiabatic temperature change from non-adiabatic measurements of temperature change induced by a field change. Our model fits efficiently temperature versus time and temperature change versus the inverse of the field change rate data for three different materials presenting different i-caloric effects. The results indicate the present model is a very useful and robust tool to obtain the correct $\Delta T_{S}$ values and to correlate $\Delta T_{S}$ with other thermodynamic quantities.

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A. M. G. Carvalho, W. Imamura. 2023-03-06. A comprehensive thermodynamic model for temperature change in i-caloric effects. https://arxiv.org/abs/2303.15292

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