Particle Agglomeration in Bipolar Barb Agglomerator Under AC Electric Field

The development of an efficient technology for removing fine particles in flue gas is essential as the haze is becoming more and more serious.To improve agglomeration effectiveness of fine particles,a dual zone electric agglomeration device consisting of a charging chamber and an agglomeration chamber with bipolar barb electrodes was developed.The bipolar barb electric agglomerator with a polar distance of 200 mm demonstrates good agglomeration effectiveness for particles with a size less than 8.0μm under applied AC electric field.An optimal condition for achieving better agglomeration effectiveness was found to be as follows：flue gas flow velocity of3.00 m/s,particle concentration of 2.00 g/m^3,output voltage of 35 kV and length of the barb of16 ram.In addition,4.0-6.0μm particles haste the best effectiveness with the variation of particle volume occupancy of-3.2.

An investigation into the deformation, movement and coalescence characteristics of water-in-oil droplets in an AC electric field

Drop-drop coalescence is important in electric dehydrators used for oil-water separation in the oil industry.The deformation degree,angle between the electric field and the center line of two drops,effects of intensities and frequencies of the electric field have been studied by analyzing droplet images.However,seldom have people investigated the movement and the relative velocity in the process of dropdrop coalescence.In this paper forces acting on a single droplet and horizontal water droplets in an AC electric field were analyzed,and experiments were carried out to investigate the deformation,movement and coalescence characteristics of droplets with white oil and water.With a micro high-speed camera system and image processing technology,the droplet images were collected and analyzed.The results indicate that the deformation is mainly affected by the electric field intensity,frequency,droplet diameter and the oil viscosity.High field strength and large diameter facilitate deformation of drops in the electric field.The effect of frequency and oil viscosity is not obvious.Higher frequency and higher oil viscosity will lead to smaller oscillation amplitude.The effect of electric field intensity and droplet diameter on oscillation amplitude is not obvious.When the center-to-center distance between droplets is large,the forces acting on droplets in the horizontal direction are mainly dipole-dipole attraction and drag forces.There is also the film-thinning force when droplets get closer.The forces are simplified and derived.Based on force analysis and Newton＇s second law,the relative movement is analyzed in different parts,and the relationship of center-to-center distance and time is in accordance with an explinear function at different stages.According to experimental data,the movement of 145 μm double droplets before coalescence can be fitted well with an explinear function at two stages.In addition,the whole movement process is investigated and can be estimated with a fourth order polynomial curve,from which the relative velocity of droplet movement can also be obtained.With an increases in electric field intensity and droplet diameter and a decrease in oil viscosity,the relative velocity increases.Only when the oil-water interfacial tension is obviously high,can it influence the relative movement significantly.The coalescence is mainly dipole coalescence and chain coalescence under influence of the AC electric field.

Effective response in nonlinear spherical coated composites under external AC and DC electric fields

By using the perturbation method, effective nonlinear direct current （DC） and alternating current （AC） responses of nonlinear composites with spherical coated inclusions randomly embedded in a host medium are studied under the action of an external electric field Ea = E0 ＋ E1 sinωt ＋ E3 sin 3ωt with different amplitudes and frequencies. The local potentials of composites at all harmonics are given in the inclusion particles and the host regions. All effective nonlinear responses to composites and the relationship between the effective nonlinear responses at all harmonics are also deduced for the spherical coated inclusions in a dilute limit.

Effective response of nonlinear cylindrical coated composites under external AC and DC electric field

This paper uses the perturbation method to study effective response of nonlinear cylindrical coated composites. Under the external AC and DC electric field Ea （1 ＋sin ωt）, the local potentials of composites at all harmonic frequencies are induced. An effective nonlinear response to composite is given for the cylindrical coated inclusions in the dilute limit.

Liquid crystal model of vesicle deformation in alternating electric fields

Considering the effects of osmotic pressure, elastic bending, Maxwell pressure, surface tension, as well as flexo-electric and dielectric properties of phospholipid membrane, the shape equation for sphere vesicle in alternation （AC） electric field is derived based on the liquid crystal model by minimizing the free energy due to coupled mechanical and AC electrical fields. Besides the effect of elastic bending, the influence of osmotic pressure and surface tension on the frequency dependent behavior of vesicle membrane in AC electric field is also discussed. Our theoretical results for membrane deformation are consistent with corresponding experiments. The present model provides the possibility to further disclose the frequency-depended behavior of biological cells in the coupled AC electric and different mechanical fields.

Effective AC response of a nonlinear spherical coated composite

An effective nonlinear response of a nonlinear composite with spherical coated inclusions randomly embedded in a host medium under the action of an external AC electric field, Ea= E1 sin（wt） ＋ E3 sin（3wt）, is investigated using a perturbation method. The local potentials of the composite at higher harmonics are given both in the region of local inclusion particles and in the local host region under the external AC electric field. All effective nonlinear responses of the composite and the relationship between the effective nonlinear responses at the fundamental frequency and third harmonics are also studied for spherical coated inclusion in a dilute limit.