scholarly journals Secondary Breakup Characteristics and Mechanism of Single Electrified Al/N-Decane Nanofluid Fuel Droplet in Electrostatic Field

2020 ◽  
Vol 10 (15) ◽  
pp. 5332
Author(s):  
Heng Lu ◽  
Shengji Li ◽  
Hongzhe Du ◽  
Yibin Lu ◽  
Xuefeng Huang
Keyword(s):  
Electric Field ◽  
Surface Charge ◽  
Electrostatic Field ◽  
Taylor Cone ◽  
Nanoparticle Concentration ◽  
Fuel Droplets ◽  
Electric Field Direction ◽  
Cone Formation ◽  
Nanofluid Fuel ◽  
Secondary Breakup

The combustion characteristics of nanofluid fuels have been widely investigated, but rare studies on the atomization were reported. Atomization is an imperative and crucial step to improve the combustion performance of nanofluid fuels, and the secondary breakup of droplets is an important segment for atomization to produce uniform fine droplets and distribute nanoparticles in each droplet. This paper firstly presents the secondary breakup characteristics of single electrified Al/n-decane nanofluid fuel droplets and revealed the mechanism of the secondary breakup. The results demonstrated that fine droplets could be produced in the electrostatic field and Al nanoparticles were distributed in each droplet. Before the breakup, the single electrified droplets experienced surface charge transportation, deformation, and Taylor cone formation. A gradient of the electric field deformed the droplet to produce the Taylor cone. As the Taylor cones were stabilized, the fluid was extruded from the tips of stable Taylor cones to produce jet filament parallel to the electric field direction and correspondingly broke up into fine sub droplets. At the nanoparticle concentration range of 1.0~10 mg/mL, the minimum average diameter of breakup sub droplets could achieve ~55.4 μm at 6.0 mg/mL. The Al nanoparticle concentration had a significant effect on the breakup performance by influencing the physical properties and charging. The order of the Charge-to-Mass ratio magnitude was 10−7~10−5 C/kg. Furthermore, the secondary breakup mechanism of single electrified nanofluid fuel droplets in the uniform electrostatic field was revealed by analyzing the droplet surface charge, deformation, Taylor cone formation, and nanoparticle concentration effect.

Transient Response of Electrostatic Field due to Collision ESD between Spherical Electrodes by using Bare-chip Optical Electric Field Sensor

2020 ◽  
Vol 140 (12) ◽  
pp. 599-600
Author(s):  
Kento Kato ◽  
Ken Kawamata ◽  
Shinobu Ishigami ◽  
Ryuji Osawa ◽  
Takeshi Ishida ◽  
...  
Keyword(s):  
Electric Field ◽  
Transient Response ◽  
Electrostatic Field ◽  
Electric Field Sensor ◽  
Field Sensor

Effects of Space Charge on ESEM Gas Amplification

1997 ◽  
Vol 3 (S2) ◽  
pp. 609-610 ◽  
Author(s):  
B.L. Thiel ◽  
M.R. Hussein-Ismail ◽  
A.M. Donald
Keyword(s):  
Electric Field ◽  
Electrostatic Field ◽  
Secondary Electron ◽  
Sample Surface ◽  
Cascade Process ◽  
Secondary Electrons ◽  
Positive Ions ◽  
Space Charges ◽  
Cascade Amplification ◽  
Environmental Sem

We have performed a theoretical investigation of the effects of space charges in the Environmental SEM (ESEM). The ElectroScan ESEM uses an electrostatic field to cause gas cascade amplification of secondary electron signals. Previous theoretical descriptions of the gas cascade process in the ESEM have assumed that distortion of the electric field due to space charges can be neglected. This assumption has now been tested and shown to be valid.In the ElectroScan ESEM, a positively biased detector is located above the sample, creating an electric field on the order of 105 V/m between the detector and sample surface. Secondary electrons leaving the sample are cascaded though the gas, amplifying the signal and creating positive ions. Because the electrons move very quickly through the gas, they do not accumulate in the specimen-to-detector gap. However, the velocity of the positive ions is limited by diffusion.

scholarly journals Uniform electric-field-induced lateral migration of a sedimenting drop

2016 ◽  
Vol 792 ◽  
pp. 553-589 ◽  
Author(s):  
Aditya Bandopadhyay ◽  
Shubhadeep Mandal ◽  
N. K. Kishore ◽  
Suman Chakraborty
Keyword(s):  
Electric Field ◽  
Surface Charge ◽  
Tilt Angle ◽  
Shape Deformation ◽  
Uniform Electric Field ◽  
Lateral Motion ◽  
Drop Surface ◽  
Lateral Migration ◽  
Drop Velocity ◽  
Pressure Fields

We investigate the motion of a sedimenting drop in the presence of an electric field in an arbitrary direction, otherwise uniform, in the limit of small interface deformation and low-surface-charge convection. We analytically solve the electric potential in and around the leaky dielectric drop, and solve for the Stokesian velocity and pressure fields. We obtain the correction in drop velocity due to shape deformation and surface-charge convection considering small capillary number and small electric Reynolds number which signifies the importance of charge convection at the drop surface. We show that tilt angle, which quantifies the angle of inclination of the applied electric field with respect to the direction of gravity, has a significant effect on the magnitude and direction of the drop velocity. When the electric field is tilted with respect to the direction of gravity, we obtain a non-intuitive lateral motion of the drop in addition to the buoyancy-driven sedimentation. Both the charge convection and shape deformation yield this lateral migration of the drop. Our analysis indicates that depending on the magnitude of the tilt angle, conductivity and permittivity ratios, the direction of the sedimenting drop can be controlled effectively. Our experimental investigation further confirms the presence of lateral migration of the drop in the presence of a tilted electric field, which is in support of the essential findings from the analytical formalism.

BRIDGING OF CARBON FIBERS IN CF/EPOXY COMPOSITES USING ELECTROSTATICALLY INDUCED CNT ALIGNMENT

2021 ◽  
Author(s):  
DANDAN ZHANG ◽  
XINGKANG SHE ◽  
YIPENG HE ◽  
WESLEY A. CHAPKIN, ◽  
VI T. BREGMAN ◽  
...  
Keyword(s):  
Carbon Fiber ◽  
Electric Field ◽  
Carbon Fibers ◽  
Hybrid Composites ◽  
Tensile Modulus ◽  
Tensile Tests ◽  
Polymer Mixture ◽  
Ac Electric Field ◽  
Reinforced Polymer ◽  
Electric Field Direction

Carbon fiber reinforced polymer (CFRP) composites are lightweight materials with superior strength but are expensive due to the increased cost of carbon fibers (CFs). The addition of carbon nanotubes (CNTs) to polymer nanocomposites are becoming an excellent alternative to CF due to their unique combination of electrical, thermal, and mechanical properties. With the application of an electric field across the CNT/polymer mixture before curing, CNTs will not only be aligned along the electric field direction, but also form networks after reaching to a certain degree of alignment. In this study, an alternating current (AC) electric field was applied continuously to CNT/CF/Epoxy hybrid composites before curing. By cutting off the applied voltage when the monitored electric current increased, the degree of networking of CNTs between two CF tows was controlled. The relative electric field strength around the end of conductive carbon fiber tows in the epoxy matrix was modeled using COMSOL Multiphysics. It increased after applying AC electric field parallel to the CF tows, thereby increasing the alignment degree of CNTs and building a network to bridge the CF tows. The preliminary results indicate that the microhardness and tensile modulus between two CF tows are increased due to the networking of CNTs in this area. The fracture surface of the specimens after tensile tests were characterized to reveal more details of the microstructure.

Calculation of Power Frequency Electric Field under Overhead Lines with Complex Ground

2013 ◽  
Vol 441 ◽  
pp. 212-216
Author(s):  
Zhen Guang Liang ◽  
Yu Ze Jiang ◽  
Di Wen Jiang ◽  
Zong Jie Liu
Keyword(s):  
Electric Field ◽  
Surface Charge ◽  
Simulation Method ◽  
Three Dimension ◽  
Charge Simulation Method ◽  
Overhead Lines ◽  
Straight Line ◽  
Power Frequency ◽  
Frequency Electric Field ◽  
Distribution Of Electric Field

This paper studied influence of three dimension complex ground on electric field under overhead lines. Surface charge method is discussed and planar triangle surface charge elements are used to represent complex ground. Electric field of overhead lines is analyzed by charge simulation method. Finite straight line charges are used to represent conductors. Then electric field of 220kV double circuit overhead lines over a three dimension small hill is calculated and distribution of electric field 1.5m above the ground is analyzed.

scholarly journals Variation of Magnetic Fluid Deformation Related to Nanoparticle Concentration in Steady Electric Field

2018 ◽  
Vol 133 (3) ◽  
pp. 570-573
Author(s):  
M. Kosterec ◽  
J. Kurimský ◽  
R. Cimbala ◽  
M. Špes ◽  
R. Farkaš ◽  
...  
Keyword(s):  
Electric Field ◽  
Magnetic Fluid ◽  
Nanoparticle Concentration

scholarly journals THE EFFECT OF ELECTRIC FIELD DIRECTION ON THE-SHEAR STRESS OF ER FLUIDS

1996 ◽  
Vol 45 (4) ◽  
pp. 640
Author(s):  
WANG ZUO-WEI ◽  
LIN ZHI-FANG ◽  
TAO RUI-BAO
Keyword(s):  
Shear Stress ◽  
Electric Field ◽  
Field Direction ◽  
Electric Field Direction ◽  
Er Fluids
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