Recherche

Afficher tous les résultats pour

Accueil

Catégorie

Chaleur (thermodynamique)

Applied sciences
Génie mécanique
Thermal engineering
Chaleur (thermodynamique)

À propos
Confidentialité
Mentions légales

Graph Chatbot

Publications associées (25)

Unearthing the foundational role of anharmonicity in heat transport in glasses

The time-honored Allen -Feldman theory of heat transport in glasses is generally assumed to predict a finite value for the thermal conductivity, even if it neglects the anharmonic broadening of vibrational normal modes. We demonstrate that the harmonic app ...

Amer Physical Soc2024

Thermoelectric power of overdoped Tl2201 crystals: charge density waves and T1 and T2 resistivities

Matthias Carsten Putzke

We report measurements of the in-plane thermoelectric power (TEP) for an overdoped (OD) crystal of the single layer cuprate superconductor Tl2Ba2CuO6+x (Tl2201) at several hole concentrations (p), from 300 or 400 K to below the superconducting transition t ...

Iop Publishing Ltd2024

Advancing efficiency and reliability in thermal analysis of laser powder-bed fusion

Christian Leinenbach, Thomas Mayer, Rafal Wróbel

In laser based powder-bed fusion of metals (PBF-LB/M), parts are fabricated by melting layers of powder using a high-intensity laser beam. During this process, the material is exposed to rapid cooling rates and intense thermal gradients, which are the unde ...

2023

Electromechanical investigations and quench experiments on sub-size HTS cables for high field EU-DEMO Central Solenoid

Ortensia Dicuonzo

The aim of this thesis is to investigate the mechanical and thermal behaviour of HTS coated conductor cables for EUROfusion DEMO magnets. One of the issue in large HTS magnets is the safety against a quench. A quench is a sudden thermal runway in which the ...

EPFL2022

Wigner Formulation of Thermal Transport in Solids

Nicola Marzari, Michele Simoncelli

Two different heat-transport mechanisms are discussed in solids. In crystals, heat carriers propagate and scatter particlelike as described by Peierls's formulation of the Boltzmann transport equation for phonon wave packets. In glasses, instead, carriers ...

American Physical Society2022

Near-junction microfluidic cooling for high power-density GaN-on-Si electronics: A wafer, device, packaging, and system-level investigation

Remco Franciscus Peter van Erp

Electrification of the energy section, from generation to end-use, plays an essential role in reducing global CO2 emission. Innovations in power electronics are required to increase conversion efficiency and power density. Gallium nitride (GaN) transistors ...

EPFL2022

Impact of the ventilated air-space behind traditional (passive) and BIPV (active) façades on the thermo-hydrodynamic performance of the building wall structures

Mohammad Rahiminejad

For many decades, ventilated cavities in wall assemblies of buildings have been essential for creating moisture-resilient constructions by allowing airflow within the air gap to promote drying. In addition to that, the airflow in the cavity can contribute ...

EPFL2022

Strong temperature-dependent thermoelectric power of IrMn(3)thin films of different thicknesses

Jean-Philippe Ansermet, Haiming Yu, Junfeng Hu, Mukund Krishna Kothari

IrMn(3)thin films were experimentally characterized by thermoelectric power and resistivity as a function of temperature and sample thickness. The Seebeck coefficient shows strong temperature dependence and the value increases with temperature up to 350 K. ...

IOP PUBLISHING LTD2021

Thermal transport beyond Fourier, and beyond Boltzmann

Michele Simoncelli

Crystals and glasses exhibit fundamentally different heat conduction mechanisms: the periodicity of crystals allows for the excitation of propagating vibrational waves that carry heat, as first discussed by Peierls in 1929, while in glasses the lack of per ...

EPFL2021

Journal of Physics: Conference Series High-pressure specific heat technique to uncover novel states of quantum matter

Henrik Moodysson Rønnow, Julio Antonio Larrea Jiménez

AC-specific heat measurements remain as the foremost thermodynamic experimental method to underpin phase transitions in tiny samples. However, its performance under combined extreme conditions of high-pressure, very low temperature and intense magnetic fie ...

IOP PUBLISHING LTD2020

Effective conductivity of porous ceramics in a radiative environment

Jérémy Raphaël Mora-Monteros, Sophia Haussener, Clemens Gregor Suter

The knowledge of the effective thermal conductivity, taking into account conduction and radiation, is crucial for the accurate prediction of the thermal behavior of porous foams, especially in an environment where radiation is dominating. We present a comb ...

2020

Unified theory of thermal transport in crystals and glasses

Nicola Marzari, Michele Simoncelli

NATURE PUBLISHING GROUP2019

Heat-transfer at the interface between a metal and a non-metal: influence of ultra-thin interlayers, interface chemistry and atomic order

Maïté Blank

The Thermal Boundary Conductance (TBC) at the interface between metals and dielectrics is of key importance for heat transport in structures heterogeneous on a scale from 100 µm downwards. In this thesis the TBC of a large number of metal/dielectric couple ...

EPFL2019

Preparation of high-conductivity, high-capacity phase change media capsules with enhanced thermos-chemical stability in thermal energy storage applications

Selmar Rudolf Binder

Thermal energy storage using the effects of the latent heat in the solid-liquid phase transformation has found its way into every day applications. Reusable, organic phase change media stabilize low temperatures of parcels, and salt/water tanks act as buff ...

EPFL2019

The influence of the incommensurately modulated structure on the physical properties of Fe1.35Ge

Helmuth Berger, László Forró, Alla Arakcheeva, Philip Pattison, Krunoslav Prsa, Jacim Jacimovic, Sergiy Katrych, Andrea Pisoni

Single crystal growth by chemical vapour transport has resulted samples with Fe1.35Ge stoichiometry. Structural study has shown that the large number of vacancies introduces an incommensuately modulated structure. The electrical resistivity is in the 200 m ...

2019

High-pressure NMR spectroscopic and calorimetric studies on formic acid dehydrogenation and carbon dioxide hydrogenation

Cornel Fink

Our current energy production is convenient and simple, but it is not sustainable. The negative impacts on our environment are omnipresent in the form of smog, extinction of species, and global warming. A major challenge of our generation is the transition ...

EPFL2018

Fast real time and quantitative gas analysis method for the investigation of the CO2 reduction reaction mechanism

Andreas Züttel, Robin Tobias Andreas Mutschler, Wen Luo, Emanuele Moioli

We present a new fast real time and quantitative gas analysis method by means of mass spectrometry (MS), which has approximately an order of magnitude faster sampling rate in comparison with a traditional gas chromatography. The method is presented and dis ...

AMER INST PHYSICS2018

Topological phonons and thermoelectricity in triple-point metals

Quansheng Wu

Recently published discoveries of acoustic- and optical-mode inversion in the phonon spectrum of certain metals became the first realistic example of noninteracting topological bosonic excitations in existing materials. However, the observable physical and ...

AMER PHYSICAL SOC2018

Accurate thermal conductivities from optimally short molecular dynamics simulations

Aris Marcolongo, Loris Ercole

The evaluation of transport coefficients in extended systems, such as thermal conductivity or shear viscosity, is known to require impractically long simulations, thus calling for a paradigm shift that would allow to deploy state-of-the-art quantum simulat ...

Nature Research2017

Thermal Modeling and Experimental Verification of an Air Cooled Medium Frequency Transformer

Marko Mogorovic, Drazen Dujic

This paper provides detailed analytical modeling and finite elements method (FEM) analysis of the thermal behavior of the medium frequency transformer (MFT). A comprehensive analytical model in form of a thermal network consisting of conduction, convection ...

Ieee2017

Page 1 sur 2