Liquid dielectric

About: Liquid dielectric is a research topic. Over the lifetime, 3702 publications have been published within this topic receiving 45150 citations.

Dynamic Evolution of Events Accompanying the Low-Voltage Discharges Employed in EDM

Abstract: Experimental studies of the evolution of events accompanying a transient, low-voltage sparkover-initiated discharge between closely-spaced electrodes in a liquid dielectric are described. The discharge parameters and the electrode configuration are similar to those found in electrical discharge machining (EDM) applications. High-speed photomicrographic records of the dynamic evolution of the discharge column and the gas bubble created by the discharge are presented. Additional photographic evidence of the details of electrode metal erosion dynamics is given. The photo-micrographs suggest that metal erosion takes place at the beginning of the discharge current pulse and after the termination of the discharge current pulse.

Near-electrode and transient processes in liquid dielectrics

Abstract: Electron transfer kinetics between an electrode and an electron acceptor in electrolytes, liquid dielectrics, and dense gases is comparatively analyzed for the case of a weak electric field. Near-electrode charge distribution patterns in a liquid dielectric (or a dense weekly conducting gas) exposed to an external high-voltage field are examined. It is shown that the quadratic dependence of current–voltage characteristics of the system is determined by the character of electron transitions from surface states. The transient processes involved are discussed, and characteristic formation times for steady-state near-electrode patterns are calculated.

Influences of electric field on living cells in a charged water-in-oil droplet under electrophoretic actuation.

Abstract: We experimentally investigate the effects of high electric field on living cells inside a charged droplet under electrophoretic actuation. When an aqueous droplet suspended in a dielectric liquid contacts with electrified electrode, the droplet acquires charge. This charged droplet undergoes electrophoretic motion under strong electric field (1–3 kV/cm), which can be used as a droplet manipulation method in biomicrofluidic applications. However, because strong electric field and use of dielectric oil can be a harmful environment for living cells, the biological feasibilities have been tested. Trypan blue test and cell growth test have been performed to check the viability and proliferation of cells in a droplet under various electric field strengths and actuation times. We have not observed any noticeable influence of electric field and silicone oil on the viability and proliferation of cells, which indicates that electrophoresis could be safely used as a manipulation method for a droplet containing living biological system.

Measurement of Dry Rubber Content in Latex Using Microwave Technique

Abstract: This paper deals with an experimental study on the dielectric properties of natural rubber as a function of dry rubber content. The cost of rubber is directly dependant on the dry rubber content and therefore the study gains its importance. It shows that the dielectric properties of Hevea latex are mainly due to the orientation of loosely bound water molecules .The experiment was done at room temperature using a dielectric liquid cell used to hold the sample of natural rubber under study. The study comes to the inference that there is an inversely proportional relationship between the dry rubber content and its dielectric constant. i.e as the moisture content increases, the dielectric constant also increases. Keywords,dielectric constant ,latex, dry rubber

PIV measurements on charged plumes-influence of SiO 2 seeding particles on the electrical behavior

Abstract: It is well known that an isothermal dielectric liquid can be driven by electroconvection. It has been demonstrated that two phenomena could generate space charge in isothermal dielectric liquids and then induce a fluid movement. These two electroconvective effects are bulk conduction and ion injection. In order to improve the performance of electroconvective devices, the velocity of the flows must be recorded as accurately and precisely as possible. In this paper, the particle image velocimetry (PIV) method that was originally developed in the field of experimental fluid mechanics is adapted to electroconvective flow measurements. The choice and the size of seeding particles are discussed. The influence of the seeding particles density on the current is measured. In this work, experiments were investigated on a typical two-dimensional charged plume flow produced between a blade and a flat plate. Both negative and positive polarities are also investigated.