Publications related to 85 W VECSEL output at 1270 nm with conversion efficiency of 59 %

Self-catalysed frontal polymerisation enables fast and low-energy processing of fibre reinforced polymer composites

Véronique Michaud, Baris Çaglar, Jacobus Gerardus Rudolph Staal

Frontal polymerisation has the potential to bring unprecedented reductions in energy demand and process time to produce fibre reinforced polymer composites. Production of epoxy-based fibre reinforced polymer parts with high fibre volume content, commonly e ...

2024

Innovative thermophysical characterization of an ATF composite cladding: the case of silicon carbide

Andrea Cavaliere

Nuclear power is a powerful technology that plays an important role in the fight against climate change, and research is continuously engaged in studies that could further improve its safety. After the Fukushima accident, Accident Tolerant Fuels research h ...

EPFL2024

Decomposition method to evaluate district heating/cooling network potential at urban scale

Luc Girardin, François Maréchal, Raphaël Briguet, Ana Catarina Gouveia Braz, Bingqian Liu

In this work, a tool to design district heating networks (DHN) is presented and applied to the city of Lausanne as a case study. The evaluation of the buildings’ heat/cooling demand is performed using a Geographic Information System (GIS) database, built f ...

Associazione Italiana Di Ingegneria Chimica2024

Design and assessment of an evaporating water-cooled methanation reactor for a SOE-based power-to-methane system

Philippe Aubin

The transition towards clean renewable energy sources, where wind and solar are prone to variation, requires adequate energy storage. Power-to-methane (PtM) systems can be part of the solution. Specifically, solid-oxide-electrolyser (SOE) based PtM systems ...

EPFL2024

Thermal conductivity of Li 3 PS 4 solid electrolytes with ab initio accuracy

Michele Ceriotti, Federico Grasselli

The vast amount of computational studies on electrical conduction in solid-state electrolytes is not mirrored by comparable efforts addressing thermal conduction, which has been scarcely investigated despite its relevance to thermal management and (over)he ...

Amer Physical Soc2024

Performance of energy piles foundation in hot-dominated climate: A case study in Dubai

Lyesse Laloui, Elena Ravera, Sofie Elaine ten Bosch

Energy piles represent an innovative technology that can help provide sustainable geothermal heating or cooling energy for thermal conditioning purposes. In hot-dominated climates, the interest is to inject heat in the ground and extract energy for space-c ...

Pergamon-Elsevier Science Ltd2024

Small-scale turbopumps for waste heat recovery applications based on an organic Rankine cycle: a study from pre-design to experimental validation

Sajjad Zakeralhoseini

The organic Rankine cycle (ORC) system is among the technologies applied to exploit waste heat in vehicles. Since common organic fluids have lower latent heat than water, higher mass flow rates are required to convert the same waste heat, considerably incr ...

EPFL2023

Multiscale enhancement of refrigerant falling film boiling by combining commercially enhanced tubes with nanostructures

John Richard Thome

Multiscale surface structures offer the opportunity to combine the heat transfer enhancement provided by microscale structures with the dryout benefits provided by some nanostructures, which is particularly attractive for falling film evaporators, who have ...

Pergamon-Elsevier Science Ltd2023

Experimental study of the hydrodynamic and thermal performances of ventilated wall structures

Mohammad Rahiminejad, Dolaana Khovalyg

The presence of a ventilated air gap behind the external cladding in a building envelope is known to have a tangible contribution to the overall performance of the wall assembly. In the present study, the hydrodynamic and thermal performances of ventilated ...

2023

Thermal Design of a Medium Voltage Modular Multilevel Converter Cell

Drazen Dujic, Yanick Patrick Frei

This paper presents the cooling concept for a medium voltage modular multilevel converter cell. To optimize power density, the metallic enclosure is used to dissipate the heat generated by semiconductor losses, while maintaining maximum temperatures below ...

New York2023

Heat transfer of uncoated and nanostructure coated commercially micro-enhanced refrigeration tubes under pool boiling conditions

John Richard Thome

The heat transfer performance of commercially produced micro-enhanced tubes with and without a nanocoating was investigated under pool boiling of saturated refrigerant. These multiscale enhancements were on the outside of 19 mm horizontal copper tubes heat ...

Pergamon-Elsevier Science Ltd2023

Cavitation induced by pulsed and continuous-wave fiber lasers in confinement

Christophe Moser, Jan Krizek

Bubbles generated with lasers in liquids under confinement have been investigated for their potential use as the driving mechanism for liquid micro-jets in various microfluidic devices, such as needle-free jet injectors. Here, we report on the study of bub ...

ELSEVIER SCIENCE INC2023

Spectroscopic characterisation of TCV divertor towards a detached regime

Lorenzo Martinelli

The challenge of power exhaust of the high heat and particle fluxes foreseen for ITER and the forthcoming nuclear fusion reactors can be mitigated by operating in a detached divertor regime. This regime has been the object of three decades of studies, as i ...

EPFL2023

Mitochondrial matrix protein LETMD1 maintains thermogenic capacity of brown adipose tissue in male mice

Johan Auwerx, Maroun Bou Sleiman, Jun Yong Kim, Xiaoxu Li

Brown adipose tissue (BAT) has abundant mitochondria with the unique capability of generating heat via uncoupled respiration. Here, Park et al. identify LETMD1 as a mitochondrial matrix protein enriched in brown adipose tissue (BAT) and reveal a crucial ro ...

Nature Portfolio2023

Beam radiation penetration in particle b e ds for heat transfer modeling of a centrifugal solar particle receiver

Serdar Hiçdurmaz, Evan Fair Johnson

This article describes a study of beam radiation striking particle beds of randomly packed, spherical par-ticles. The current study is focused on concentrating solar power receivers which use solid particles as a heat transfer medium, but results are appli ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Improved Waste Heat Management and Energy Integration in an Aluminum Annealing Continuous Furnace Using a Machine Learning Approach

François Maréchal, Manuele Gatti, Daniel Alexander Florez Orrego, Réginald Germanier, Mohammad Andayesh

Annealing furnaces are critical for achieving the desired material properties in the production of high-quality aluminum products. In addition, energy efficiency has become more and more important in industrial processes due to increasing decarbonization r ...

2023

Laser-Induced Forward Transfer of Functional Microdevices

Zhiwei Yang

Laser-induced forward transfer (LIFT) technique is an emerging micro additive manufacturing (AM) technique that has been widely used to print a variety of materials. Distinguished from other nozzle-based AM techniques, LIFT operates without the existence o ...

EPFL2023

Self-injection Locked Second-Harmonic Generation in Optically Poled Silicon Nitride Microresonators

Tobias Kippenberg, Camille Sophie Brès, Junqiu Liu, Edgars Nitiss, Marco Clementi

We present a narrow-linewidth second-harmonic source based on a laser diode injection locked to an optically poled silicon nitride microresonator. The device is a compact, highly-coherent dual-wavelength source, with high conversion efficiency up to 280%/W ...

2023

High-speed turbocompressors for natural fluid heat-pumps: from integrated design to digital-twin

Luis Eric Olmedo Ocampo

Compressors for commercial and industrial heat-pumps in the 100kW-load range are currently dominated by positive displacementmachines. In the context of refrigerant phaseouts and changing regulations, natural refrigerants are seen as a compelling alternati ...

EPFL2023

Radiation-tolerant Multichannel Dew Point Temperature Monitoring System for High Energy Physics Applications

Amar Kapic

The next generation of high-energy physics (HEP) detectors will predominantly be silicon-based. As pixel sensor technology gains momentum and the number of channels surpasses one billion (for a volume of approximately 20 m3) to achieve the high resolution ...

EPFL2023