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4-6 Jul 2023 Cherbourg en Cotentin (France)
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French Society of Electrostatic
The solution of an electrostatic problem: the lightning rod umbrella Many people think that electrostatics is a mysterious science that makes people's hair ruffle on the head! Certainly, but a photocopier or an inkjet printer also work on the same principle. Finally, this science is present in everyday life applications and many times... we ignore it! Electrostatics studies the interactions between the electric charges of an object considering that they are (almost) immobile to the eyes of the observer. Its phenomena have been visible to mankind since immemorial times: lightning is the most usual example. But since ancient times, the Greeks had noticed that a piece of amber previously rubbed against a cloth attracted light materials that stuck on it. This phenomenon is now perfectly described by electrostatics. The Greek word for amber, ήλεκτρον, ("elektron") is the root word for the elementary particle that constitutes atoms. It is the root of many scientific disciplines so one can say that electrostatics is the mother of all sciences related to electricity. Electrostatics can be found at any scale and in many fields, both natural and industrial. The Laboratoire Universitaire des Sciences Appliquées de Cherbourg leads researches related to electrostatics with the collaboration of industrial companies (ACOME, EXXELIA, ...). For example in the field of electrical energy storage and electricity transport: - The capacitor is a usual passive component. Its function is to store electrical energy on its electrodes. Its performance depends mainly on the electrostatic properties of its dielectric material. - The supercapacitor holds an increased storage capacity due to the electrostatic-double-layers observed on its armatures - The insulating sheath of an electric cable meets the requirements of a severe specification. Electrostatic criteria are used to determine these parameters. However, electrostatics can be found in other sectors related to the environment such as smoke purification, air purification, or selective sorting for plastic recycling, etc. Indeed, an electrostatic filter is a system that actively eliminates dust and smoke from a gas. The particles to be eliminated are electrically charged and then pushed toward an electrode due to an electric field for being collected. It is an efficient system that never clogs. Similarly, plastic granules from waste sites are separated to be recycled according to their different formulations using an electrostatic sorting process. Electrostatics is also involved for preventing industrial risks. When two materials are rubbed together, electrical charges build up on the surface of the objects and can a so high level that they cause an electrical discharge (a spark). If this occurs in an explosive atmosphere, it can cause ignition or even an explosion. This phenomenon can occur in various situations: the flow of a liquid in a pipe, the transfer of a bulk product or powder, the impact of particles on the wall of a separator, the movement of a person on the floor, etc. The more insulating the material is, the more the charges accumulate. Many industries are concerned, even those that would not be suspected: handling an electronic chip without precaution can destroy it because of the electrostatic discharges in its core! Finally, electrostatics is present in natural meteorological phenomena that still terrify mankind today: a thundercloud accumulates electrical charges at different altitudes that are brutally discharged forming a lightning strike. This is the raison d'être of the Société Française d'Electrostatique, a scholarly society created 25 years ago. It gathers teachers, researchers, and industrials concerned by electrostatic questions and organizes every two years a French-speaking conference in a university city where this discipline is the topic of research. Thus Poitiers, Montpellier, Toulouse, Grenoble, Paris, and Cherbourg have regularly hosted an edition of this conference.
Jean-Michel REBOUL Société Française d'Electrostatique TELEPORT 2 FUTUROSCOPE F-86360 CHASSENEUIL-DU-POITOU |
