Electrohydrodynamic Pump Supplied by Unipolar Direct Current Voltage With Both Positive and Negative Corona Discharge

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
Janusz Podliński ◽  
Magdalena Danowska ◽  
Tomasz Izdebski ◽  
Mirosław Dors
Keyword(s):  
Electric Field ◽  
Corona Discharge ◽  
Gas Flow ◽  
Strong Electric Field ◽  
High Ratio ◽  
Parallel Plates ◽  
Particle Image Velocimetry Technique ◽  
Time Resolved ◽  
Direct Current Voltage ◽  
Gas Pumping

Strong electric field applied between the two electrodes initiates a corona discharge, which results in ionization of gas molecules and induces ionic wind, also known as the electrohydrodynamic (EHD) flow. If an electric field is asymmetric, then a unidirectional gas flow can be formed causing so-called EHD gas pumping. In spite of many experiments with different electrode shapes and configurations such as needle-to-mesh, needle-to-ring, wire-to-rod, wire-to-non-parallel plates, etc., aimed at production of intensive gas pumping, the investigated EHD pumps were most often unsatisfactory. In our research, we proposed a new configuration of electrodes for the EHD pump, where all electrodes (excluding the first one and the last one) are simultaneously the discharge (on one side) and the collecting (on the other side) electrodes. Our electrodes configuration can be easily multiplied without additional space between consecutive electrodes. In such a case, a high ratio of pumping efficiency to pump size can be obtained. The Time-Resolved Particle Image Velocimetry technique was used to investigate the EHD flow generated by our EHD pump.

Ozone Gas Generator Using Uniaxially Polarized LiTaO3 Single Crystal

2007 ◽  
Vol 1034 ◽  
Author(s):  
Nakanishi Yoshikazu ◽  
Junko Ide ◽  
Jun Kondo ◽  
Shinji Fukao ◽  
Katsumi Handa ◽  
...  
Keyword(s):  
Electric Field ◽  
Single Crystal ◽  
Temperature Change ◽  
Atmospheric Pressure ◽  
Gas Flow ◽  
Strong Electric Field ◽  
Ozone Production ◽  
Maximum Temperature ◽  
Gas Generator ◽  
Non Equilibrium

AbstractThe phenomenon that a ferroelectrics crystal carries out intrinsic polarization by the temperature change generally is known. The Ozone gas generation was investigated due to a strong electric field of this crystal under atmospheric pressure . When we added a rapid temperature change to the crystal, the charge non–equilibrium occurs around the crystal. Oxygen is influenced due to the non-equilibrium in charge and ozone is considered to be generated. Therefore, we used the high electric field induced due to the polarization of a ferroelectrics crystal in order to produce the ozone under atmospheric pressure.As a result, we were able to produce ozone of the density of 400ppb in a oxygen gas flow of 1.5 liters per minute using this simple system: The crystals (Yamaju Co. Ltd. and Sumitomo metal mining Co. Ltd.) are used in thickness of 3, 5, 7, 10, 20, and 30 mm with a diameter of 4 inches, respectively. They are poled crystals.Experiments on the maximum temperature (300 degree), the temperature gradient (100 degree/10 minite), and substrate materials(Cu and Al), the thickness of the crystal, and z face etc. were carried out during the temperature of LiTaO3 single crystal from 20C to about 300C. It is found that the amount of the ozone production increases rapidly, when the maximum temperature of LiTaO3 single crystal is raised and have a relation with the thickness of the crystal. However, the amount of the ozone production doesn't closely related with the X-ray generation that we use the crystal for.In the present study, when the thickness of the crystal became large, polarization voltage became high, but generated efficiency of ozone was not necessarily proportional to thickness.

Multi-Stage Collector Design and Applications

2003 ◽  
Author(s):  
Henry V. Krigmont
Keyword(s):  
Electric Field ◽  
Corona Discharge ◽  
Gas Flow ◽  
Uniform Electric Field ◽  
Two Stage ◽  
Current State ◽  
Fine Particulate ◽  
Multi Stage ◽  
Corrugated Plates ◽  
Particulate Control

The Multi Stage Collector (MSC™) concept for ultra-fine particulate control not only retains the best advantages of current state-of-the-art technology but also makes significant improvements. The new MSC™ design provides a synergistic combination of both single- and two-stage electrostatic precipitation while incorporating an additional collector-stage by filtering the gas exiting the collector through a barrier collector-zone. This arrangement ensures that essentially all dust would be detained in this final stage. The MSC™ contains multiple narrow and wide zones formed by a plurality of parallel corrugated plates. Enclosed in the narrow zones are discharge electrodes. These electrodes provide a non-uniform electric field leading to corona discharge. The corona discharge causes particulate matter in the gas flow to become charged. Wide regions contain barrier filters thus creating the two-stage precipitator with relatively uniform electric field. In these regions, particles are collected on both plates and on the porous barrier elements, which also act as the final filtering stage. Results of the applications analyses and future development work are discussed. The gas flow analyses with an aid of the CFD model are presented below.

Time-resolved X-ray reciprocal space mapping of the crystal under external electric field

2018 ◽  
Vol 189 (02) ◽  
pp. 187-194 ◽  
Author(s):  
Nikita V. Marchenkov ◽  
Anton G. Kulikov ◽  
Ivan I. Atknin ◽  
Arsen A. Petrenko ◽  
Alexander E. Blagov ◽  
...  
Keyword(s):  
Electric Field ◽  
External Electric Field ◽  
Space Mapping ◽  
Reciprocal Space ◽  
Reciprocal Space Mapping ◽  
Time Resolved ◽  
X Ray

scholarly journals Axion assisted Schwinger effect

2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Valerie Domcke ◽  
Yohei Ema ◽  
Kyohei Mukaida
Keyword(s):  
Electric Field ◽  
Production Rate ◽  
Strong Electric Field ◽  
Background Field ◽  
Chiral Anomaly ◽  
Fermion Mass ◽  
Anomaly Equation ◽  
Electric And Magnetic Fields ◽  
Schwinger Effect ◽  
Momentum Transverse

Abstract We point out an enhancement of the pair production rate of charged fermions in a strong electric field in the presence of time dependent classical axion-like background field, which we call axion assisted Schwinger effect. While the standard Schwinger production rate is proportional to $$ \exp \left(-\pi \left({m}^2+{p}_T^2\right)/E\right) $$ exp − π m 2 + p T 2 / E , with m and pT denoting the fermion mass and its momentum transverse to the electric field E, the axion assisted Schwinger effect can be enhanced at large momenta to exp(−πm2/E). The origin of this enhancement is a coupling between the fermion spin and its momentum, induced by the axion velocity. As a non-trivial validation of our result, we show its invariance under field redefinitions associated with a chiral rotation and successfully reproduce the chiral anomaly equation in the presence of helical electric and magnetic fields. We comment on implications of this result for axion cosmology, focussing on axion inflation and axion dark matter detection.

scholarly journals Spectroscopic analysis of high electric field enhanced ionization in laser filaments in air for corona guiding

2016 ◽  
Vol 4 ◽  
Author(s):  
Yingxia Wei ◽  
Yaoxiang Liu ◽  
Tie-Jun Wang ◽  
Na Chen ◽  
Jingjing Ju ◽  
...  
Keyword(s):  
Experimental Study ◽  
Femtosecond Laser ◽  
Electric Field ◽  
Corona Discharge ◽  
High Voltage ◽  
Fluorescence Spectra ◽  
Spectroscopic Analysis ◽  
Laser Pulses ◽  
Spectroscopic Measurement ◽  
High Electric Field

We report on a systematic experimental study on the fluorescence spectra produced from a femtosecond laser filament in air under a high electric field. The electric field alone was strong enough to create corona discharge (CD). Fluorescence spectra from neutral and ionic air molecules were measured and compared with pure high-voltage CD and pure laser filamentation (FIL). Among them, high electric field assisted laser FIL produced nitrogen fluorescence more efficiently than either pure CD or pure FIL processes. The nonlinear enhancement of fluorescence from the interaction of the laser filament and corona discharging electric field resulted in a more efficient ionization along the laser filament zone, which was confirmed by the spectroscopic measurement of both ionization-induced fluorescence and plasma-scattered 800 nm laser pulses. This is believed to be the key precursor process for filament-guided discharge.

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