Publications related to Polarized Linear Motor Combined With Levitation Actuators Working in a Partial Vacuum Environment — Application to Swissmetro

A Review of Modeling, Design and Performance Assessment of Linear Electromagnetic Motors for High-Speed Transportation Systems

André Hodder, Mario Paolone, Lucien André Félicien Pierrejean, Simone Rametti

Linear electromagnetic motors (LEMs) have been proposed, developed and used to propel high-speed (i.e. speed > 100 m/s) levitating vehicles. However, few real implementations have demonstrated the feasibility of these machines at such speeds. Furthermore, ...

2024

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

High energy-density electrostatic actuators for soft robotics

Sylvain Thomas Schaller

This thesis reports high energy-density electrostatic actuators for use in soft robotics. This thesis has two main parts: a) a detailed study of electro-adhesion using microfabricated electrodes, and b) a flexi-ble fiber-shaped linear motor. Electro-adhesi ...

EPFL2024

Computational fluid dynamics simulations of the heat transfer properties of graphene-based nanolubricants and application to hydrodynamic lubrication

Roberto Guarino

In this paper, we consider experimental data available for graphene-based nanolubricants to evaluate their convective heat transfer performance by means of computational fluid dynamics (CFD) simulations. Single-phase models with temperature-dependent prope ...

Aip Publishing2024

Pseudo-Three-Dimensional Analytical Model of Linear Induction Motors for High-Speed Applications

André Hodder, Mario Paolone, Lucien André Félicien Pierrejean, Simone Rametti

Literature on linear induction motors (LIMs) has proposed several approaches to model the behavior of such devices for different applications. In terms of accuracy and fidelity, field analysis-based models are the most relevant. Closed-form or numerical so ...

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

Active Power Decoupling for Single-Phase Input-Series-Output-Parallel Solid-State Transformers

Drazen Dujic, Tianyu Wei, Andrea Cervone

Solid-state transformers with input-series outputparallel structures are being considered for a variety of applications requiring MVAC to LVDC conversion. Due to the singlephase AC/DC conversion at the input side, all floating cells of the solid-state tran ...

2024

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

Stability Analysis of Input-Series/Output-Parallel Solid-State Transformers Equipped with Second-Order Harmonic Active Power Filters

Drazen Dujic, Tianyu Wei, Andrea Cervone

Solid-State Transformers with Input-Series/Output-Parallel configuration offer a convenient solution for AC/DC conversion due to their scalability and modularity. In this configuration, each module experiences a second-order harmonic ripple caused by local ...

2024

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

Laser Doppler Vibrometer measurements of the 3D pressure field for the estimation of the radiation force produced by an acoustic standing-wave levitator

Amit Yedidia Dolev

Acoustic levitation devices use powerful ultrasonic standing waves to levitate objects in mid-air. We have created a system and method to measure the full harmonic content of the acoustic field accurately. Our study revealed that levitated particles alter ...

Elsevier Science Sa2024

Computational design and additive manufacturing of electromagnetic coils

Adrien Jean-Michel Thabuis

The modern world is heavily reliant on electromagnetic devices to convert mechanical energy into electrical energy and vice versa. These devices are fundamental to powering our society, and the growing need for automated production lines and electrified tr ...

EPFL2023

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

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

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

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

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

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

Coupled Rotary and Oscillatory Motion in a Second-Generation Molecular Motor Pd Complex

Lukas Pfeifer

Molecular machines offer many opportunities for the development of responsive materials and introduce autono-mous motion in molecular systems. While basic molecular switches and motors carry out one type of motion upon being exposed to an external stimulus ...

AMER CHEMICAL SOC2023