Publications associées à Streamer discharge

Inversing the actuation cycle of dielectric elastomer actuators for a facial prosthesis

Yves Perriard, Yoan René Cyrille Civet, Paolo Germano, Alexis Boegli, Thomas Guillaume Martinez, Stefania Maria Aliki Konstantinidi, Quentin Philippe Mario De Menech

Dielectric Elastomer Actuators (DEAs) are a type of smart material described as compliant capacitors. They show impressive performances as soft actuators, such as a high strain and fast response. Nonetheless, replicating natural muscle function with DEAs h ...

Society of Photo-Optical Instrumentation Engineers (SPIE)2024

Positive Streamer Initiation in SF6/CO2 Based on Zener's Field Ionization

Guang-Yu Sun

In this study, experiments were performed to measure the inception and breakdown voltages of SF6/CO2 mixed gases with varying mixing ratios at two different pressures (1 and 2 bar). Using the preliminary data obtained from the experiments, a 3D particle mo ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Laser-guided lightning

Marcos Rubinstein, Antonio Sunjerga, Farhad Rachidi-Haeri, Amirhossein Mostajabi, Jean-Pierre Wolf, Clemens Herkommer, Pierre Walch, Thomas Produit, Victor Moreno

Lightning discharges between charged clouds and the Earth’s surface are responsible for considerable damages and casualties. It is therefore important to develop better protection methods in addition to the traditional Franklin rod. Here we present the fir ...

Nature Publishing Group2023

The Geometry and Charge of the Streamer Bursts Generated by Lightning Rods under the Influence of High Electric Fields

Farhad Rachidi-Haeri, Marcos Rubinstein

The streamer bursts generated during the initiation and propagation of leaders play an important role in the creation and maintenance of hot discharge channels in air. The most important parameters related to streamer bursts in this respect are the length ...

2022

Performance and Design of a Stepped Spillway Aerator

Anton Schleiss, Michael Pfister, Stéphane Christian Olivier Terrier

Stepped spillways are frequently limited to specific discharges under around 30 m2/s due to concerns about potential cavitation damages. A small air concentration can prevent such damages and the design of bottom aerators is well established for smooth chu ...

2022

On the Ohmic-dominant heating mode of capacitively coupled plasma inverted by boundary electron emission

Guang-Yu Sun, Haomin Sun

Electron emission from the boundary is ubiquitous in a capacitively coupled plasma (CCP) and precipitates nonnegligible influence on the discharge properties. Here, we present Particle-in-Cell/Monte Carlo Collision simulation of an Ohmic-dominant heating m ...

AIP American Institute of Physics2022

Hard and Soft Switching Losses in Power Converters: Role of Transistor Output Capacitance

Palliyage Srilak Nirmana Perera

To best utilize power converters, a sound understanding of the relationship between the circuit topology and the power-semiconductor-device characteristics is required. This is especially important in high-frequency switching, where device parasitics start ...

EPFL2022

Flood of 23 November 2019 on the French Riviera: a comparison of discharges estimated by image analysis and hydrological modelling

Gauthier Paul Daniel Marie Rousseau, Etienne Robert

The short and heavy rainfall events observed on the French Riviera often lead to flash floods on coastal catchments: during the flood of 2 October 2015, a peak discharge between 185 and 295 m(3)/s was estimated on the Brague at Biot at 8:00 PM, whereas the ...

ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD2022

Detrainment and braking of snow avalanches interacting with forests

Johan Alexandre Philippe Gaume, Xingyue Li, Louis Jean Henri Vedrine

Mountain forests provide natural protection against avalanches. They can both prevent avalanche formation in release zones and reduce avalanche mobility in runout areas. Although the braking effect of forests has been previously explored through global sta ...

COPERNICUS GESELLSCHAFT MBH2022

Preliminary Design of a High Current R&W TF Coil Conductor for the EU DEMO

Pierluigi Bruzzone, Kamil Sedlák, Federica Demattè

Paschen failures in ITER, W7-X and JT60 superconducting coils at the acceptance tests have shown that it is highly desirable to lower the coil discharge voltage (U-d) of the DEMO Toroidal Field (TF) coils. Another benefit of lowering the U-d might be the r ...

IEEE Institute of Electrical and Electronics Engineers2022

The Influence of O-2 on Positive Streamer Initiation in Supercritical CO2 With Field Ionization Using a 3-D Particle Model

Guang-Yu Sun

In this work, the influence of varying mixing ratios of O-2 on positive streamer initiation in supercritical (SC) CO2 at different applied voltages was investigated using a 3-D particle model. Zener's model was included in the 3-D particle model to calcula ...

2021

A statistical approach for the automatic identification of the start of the chain of events leading to the disruptions at JET

Alessandro Pau

This paper reports an algorithm to automatically identify the chain of events leading to a disruption, evaluating the so-called reference warning time. This time separates the plasma current flat-top of each disrupted discharge into two parts: a non-disrup ...

IOP Publishing Ltd2021

Ionization Waves Enhance the Production of X-rays during Streamer Collisions

Farhad Rachidi-Haeri, Marcos Rubinstein

Experimental data show that in laboratory sparks, X-rays are produced in time synchronization with the meeting of streamers of opposite polarity just before the final breakdown of the discharge gap. It has been suggested that the electric field enhancement ...

2021

Parametric study of the TF coil design for the European DEMO

Pierluigi Bruzzone, Kamil Sedlák, Rainer Wesche, Roberto Guarino

In addition to a reduced number of feeders, which would simplify their integration in the cryostat of the tokamak, the present study considers the possibility to reduce the voltage during safety discharge of the toroidal field (TF) coils. A lowered dischar ...

2021

Enhanced Room-Temperature Ionic Conductivity of NaCB11H12 via High-Energy Mechanical Milling

Laura Piveteau, Claudia Esther Avalos, Radovan Cerny, Matteo Brighi

The body-centered cubic (bcc) polymorph of NaCB11H12 has been stabilized at room temperature by highenergy mechanical milling. Temperature-dependent electrochemical impedance spectroscopy shows an optimum at 45-min milling time, leading to an rt conductivi ...

AMER CHEMICAL SOC2021

A fast-moving Langmuir probe array for the divertor of the Tokamak à Configuration Variable

Hugo De Oliveira

In next step tokamaks such as ITER and future fusion power plants, wall materials will be subjected to considerably higher heat and particle fluxes than in present-day machines. Maintaining plasma facing components in good condition and simultaneously assu ...

EPFL2021

On The Efficiency Of Energy Storage Systems - The Influence Of The Exchanged Power And The Penalty Of The Auxiliaries

Alfred Rufer

Storage is an important domain of the energy sector, with its traditional, classical solutions for smaller and larger amounts of energy. Energy storage has become of higher importance in relation with the development of alternative energy sources, leading ...

UNIV NIS2021

Pressure on obstacles induced by granular snow avalanches

Michael Lukas Kyburz

The increasing population and the consequential demand for dwelling and recreation areas lead to more frequent conflicts between humans and natural hazards. In mountainous regions snow avalanches are, therefore, still a major threat to humans and infrastru ...

EPFL2021

Modeling Compact Intracloud Discharge (CID) as a Streamer Burst

Farhad Rachidi-Haeri, Marcos Rubinstein

Narrow Bipolar Pulses are generated by bursts of electrical activity in the cloud and these are referred to as Compact Intracloud Discharges (CID) or Narrow Bipolar Events in the current literature. These discharges usually occur in isolation without much ...

2020

Real-time applications of Electron Cyclotron Emission interferometry for disruption avoidance during the plasma current ramp-up phase at JET

Matteo Fontana

Data produced by an electron cyclotron interferometer diagnostic are now available to the real-time control systems of of the joint European torus (JET) tokamak. The data consist of absolutely calibrated electron temperature profiles, covering the plasma l ...

2020