We report on the solution of the heat equation, which describes the electrocaloric effect in a ferroelectric layer. The dependence of the heat flux at the layer interface and the thermodynamic efficiency on the shape and frequency of the applied pulse is investigated. According to the calculations, the dependence of the efficiency on the frequency for a rectangular and sinusoidal pulse has a markedly different character. The maximum efficiency at 0.74 is achieved by a sinusoidal impulse at a frequency of 77.6 mHz. The new approach allows for better optimization of the cooling system. To model a heat switch, it is proposed to use a change in the Biot number over time. Theoretical calculations are compared with experimental results for a 0.5-mm-thick barium titanate plate. The maximum heat flux that can be created for a given plate under an electric field of 2 MV/m with an ideal heat switch turned out to be equal 120.72 W/m.
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http://dx.doi.org/10.1109/TUFFC.2020.3019251 | DOI Listing |
Int J Environ Res Public Health
November 2024
Wits Planetary Health Research, University of the Witwatersrand, Johannesburg 2193, South Africa.
Climate change is among the greatest threats to health in the 21st century, requiring the urgent scaling-up of adaptation interventions. We aim to summarise adaptation interventions that were funded by the Belmont Forum and the European Union, the largest global funders of climate change and health research. A systematic search was conducted (updated February 2023) to identify articles on adaptation interventions for health within this funding network.
View Article and Find Full Text PDFJ Phys Condens Matter
January 2025
Department of Mechanical Engineering, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada, 89557-0312, UNITED STATES.
In nonmetallic crystals, heat is transported by phonons of different frequencies, each contributing differently to the overall heat flux spectrum. In this study, we demonstrate a significant redistribution of heat flux among phonon frequencies when phonons transmit across the interface between dissimilar solids. This redistribution arises from the natural tendency of phononic heat to re-establish the bulk distribution characteristic of the material through which it propagates.
View Article and Find Full Text PDFSci Rep
January 2025
School of Mechanical Engineering, Center of Excellence in Energy Conversion, Sharif University of Technology, Tehran, Iran.
Dropwise condensation (DWC) is a widely studied vapor-liquid phase-change process that has attracted significant research attention due to its exceptional energy transfer efficiency. Therefore, it is highly important to predict the heat transfer rate during DWC and the factors that affect it. This study presents a computational fluid dynamics (CFD) investigation on DWC heat transfer under diverse circumstances for a single droplet on inclined and rough surfaces with Wenzel structure.
View Article and Find Full Text PDFChemosphere
December 2024
Department of Safety, Health and Environmental Engineering, Ming Chi University of Technology, New Taipei City 243303, Taiwan, ROC; Center for Sustainability and Energy Technologies, Chang Gung University, Taoyuan 33323, Taiwan, ROC; Biochemical Technology R&D Center, Ming Chi University of Technology, New Taipei City, 24301, Taiwan, ROC; Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chiayi 61363, Taiwan, ROC. Electronic address:
Large amounts of wastewater are produced from semiconductor manufacturing, and the production energy consumption has skyrocketed with its global demand in recent years. Forward osmosis (FO) provides unique merits in reclaiming the wastewater if suitable draw solutes with high water flux, low leakage, and limited energy requirement in regeneration are available. Two lower critical solution temperature-ionic liquids (LCST-ILs), tetrabutylphosphonium trimethylbenzensulfonate ([P][TMBS]) and tetrabutylphosphonium maleate ([P][Mal]) were synthesized and systematically assessed as recycled draw solutes in FO for the water reclamation from the wastewater of Si-ingot sawing.
View Article and Find Full Text PDFSci Adv
January 2025
State Key Laboratory of Lithospheric and Environmental Coevolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China.
The evolution of the lunar magnetic field can reveal the Moon's interior structure, thermal history, and surface environment. The mid-to-late-stage evolution of the lunar magnetic field is poorly constrained, and thus, the existence of a long-lived lunar dynamo remains controversial. The Chang'e-5 mission returned the heretofore youngest mare basalts from Oceanus Procellarum uniquely positioned at midlatitude.
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