Publications associées à Boiling of New Refrigerants: a State-of-the-Art Review

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

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

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

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

Flow Boiling of Carbon Dioxide at Different Channel Orientations for the Thermal Management of Future Detector Technologies at the High-Luminosity Large Hadron Collider at CERN

David Schmid

The global warming potential (GWP) of working fluids in thermodynamic cycles and their environmental impact have been gaining considerable attention within the recent years. The global objectives on climate protection are becoming increasingly ambitious, w ...

EPFL2022

A parametric study on pool boiling heat transfer and critical heat flux on structured surfaces with artificial cavities

Luis Guillermo Villanueva Torrijo, Ahmad Reza Motezakker

Emerging applications in new generation electronic devices require effective heat removal and thermal man-agement. In this regard, boiling is a phase change phenomenon capable of dissipating a large amount of heat compared to the sensible heat. In this stu ...

PERGAMON-ELSEVIER SCIENCE LTD2022

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

Flow pattern observations and flow pattern map for adiabatic two-phase flow of carbon dioxide in vertical upward and downward direction

Jürg Alexander Schiffmann, Rémi Revellin, David Schmid

A test facility to investigate flow pattern transitions of vertical two-phase flow of CO2 has been built within the scope of the high-luminosity detector upgrades at the European Organization for Nuclear Research (CERN). Adiabatic flow pattern observations ...

2022

Flow boiling heat transfer and two-phase flow phenomena of CO2 in macro-and micro-channel evaporators: Fundamentals, applications and engineering design

John Richard Thome

The paper presents a comprehensive review of fundamentals and engineering applications of CO2 flow boiling heat transfer, flow patterns and two-phase pressure drops in macro- and micro-channel evaporators. First, distinctions of macro- and micro-channels a ...

PERGAMON-ELSEVIER SCIENCE LTD2021

Novel pulsating heat pipe for high density power data centres: performance and flow regime analysis

John Richard Thome, Jackson Braz Marcinichen, Raffaele Luca Amalfi, Filippo Cataldo

With the advancement of technologies such as Artificial Intelligence and 5G telecommunications, where computational rate is constantly pushing its limits, highly efficient and reliable cooling devices are starting to become an overly critical factor. Not o ...

IEEE2021

Simulation and experimental validation of pulsating heat pipes

John Richard Thome, Jackson Braz Marcinichen, Filippo Cataldo, Philippe Aubin

The one-dimensional transient numerical code of JJ Cooling Innovation has been significantly improved to simulate the thermal/hydraulic performance of pulsating heat pipes (PHPs). Using a mechanistic approach, the liquid slug and vapor plug flows and their ...

PERGAMON-ELSEVIER SCIENCE LTD2021

Influencing factors on flow boiling of carbon dioxide in enhanced tubes and comparison with correlations

John Richard Thome

Carbon dioxide two-phase flow characteristics are different from those of conventional refrigerants, due to the CO2 particular thermodynamic and transport properties obtained by working at high reduced pressures. Moreover, the use of peculiar heat transfer ...

IOP PUBLISHING LTD2020

Buoyancy-driven melting and solidification heat transfer analysis in encapsulated phase change materials

Sophia Haussener, Nithin Mallya

Controlled melting and solidification in encapsulated phase change materials (PCMs) is of practical interest, for example, in latent heat storage applications. The choice of PCMs and the dynamic heat transfer characteristics during phase change - affecting ...

2021

Impact of large tip clearance ratios on the performance of a centrifugal compressor

Jürg Alexander Schiffmann, Markus Diehl

Ultra-compact and fast spinning turbomachinery is a key technology to increase performance of domestic heating applications and to address decentralization of power and heat as a consequence of the rise of renewable energy sources. Recently, a heat pump us ...

2019

Fundamental Issues, Technology Development, and Challenges of Boiling Heat Transfer, Critical Heat Flux, and Two-Phase Flow Phenomena with Nanofluids

John Richard Thome

This paper presents a comprehensive and critical review of studies on nucleate pool boiling heat transfer, flow boiling heat transfer, critical heat flux (CHF), and two-phase flow phenomena with nanofluids. First, general analysis of the available studies ...

TAYLOR & FRANCIS INC2019

Cfd-Based Correlation For Forced Convection Heat Transfer In Circular Ducts Of Internally Heated Molten Salts

Carlo Fiorina

Heat transfer phenomena involving internally heated fluid flows are of particular interest in several industrial applications, in chemical plants as in the nuclear field. This topic is relevant for the development of the Molten Salt Reactors (MSRs) since i ...

AMER SOC MECHANICAL ENGINEERS2018

Experimental characterisation of the thermohydraulic performance of a micro-pin fin evaporator: Heat transfer, flow visualization and modelling

Chiara Falsetti

The global tendency towards miniaturization driven by the microelectronics industry is pushing system density and packaging towards unprecedented values of thermal design power, with a dramatic reduction of the surface area of the devices. Vertical integra ...

EPFL2018

Flow Boiling Heat Transfer and Pressure Drops of R1234ze(E) in a Silicon Micro-pin Fin Evaporator

John Richard Thome, Mirco Magnini, Chiara Falsetti

The development of newer and more efficient cooling techniques to sustain the increasing power density of high-performance computing systems is becoming one of the major challenges in the development of microelectronics. In this framework, two-phase coolin ...

Asme2017

An updated three-zone heat transfer model for slug flow boiling in microchannels

John Richard Thome, Mirco Magnini

This work proposes a novel physics-based model for the fluid mechanics and heat transfer associated with slug flow boiling in horizontal circular microchannels to update the widely used three-zone model of Thome et al. (2004). The heat transfer model has a ...

Pergamon-Elsevier Science Ltd2017

Pressure drop prediction in annular two-phase flow in macroscale tubes and channels

John Richard Thome, Andrea Cioncolini

A new prediction method for the frictional pressure drop in annular two-phase flow is presented. This new prediction method focuses on the aerodynamic interaction between the liquid film and the gas core in annular flows, and explicitly takes into account ...

Pergamon-Elsevier Science Ltd2017

Replicated microcellular aluminium structures for thermal management

Alexandros Athanasiou-Ioannou

Open-pore aluminium foams are of interest in thermal management of power electronics due to their large specific surface area, low weight and relatively high thermal conductivity. The replication process is a low-cost and simple foam manufacturing method t ...

EPFL2017