• 한국분무공학회지
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• 제5권3호
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• pp.45-54
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• 2000

A novel electrostatic splaying method for solidifying a galvanized coating layer was studied. Our experimental results and computer simulations showed that electric field could assist the fine droplets to attach on the steel surface and change the sprayed droplets trajectory especially in the space near the steel surface. It was necessary to apply the electric voltage higher than - 20 kV to obtain the enough electrostatic attraction force between droplets and the steel sheet.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.435-435
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• 2014

Eu(III)-doped Y2O3 nanorods were deposited onto a Si substrate using electrostatic spray system. The photoluminescence imaging profiles were compared between the electrospray film and powder form. Using electrostatic spraying technique is very advantageous to generate a uniform monolayer film without much clustering of nanorods. Strong emission peaks were observed between 580 and 730 nm in response to an indirect excitation transition. Our results indicate that the electrospray technique could be very useful for generating thin films for displays and sensors.

• 대한환경공학회지
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• 제27권12호
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• pp.1292-1297
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• 2005

상수나 하수처리장에서 쓰이는 오존처리는 물질전달에 제약을 받는 공정임은 알려져왔다. 이런 물질전달의 한계를 극복하는 방법으로 매우 효과적인 것은 오존가스를 함유한 기포의 크기를 줄임으로써 물질전달에 필요한 접촉면적을 넓히는 것이다. 오존의 전달을 크게 하기 위한 방법으로서 본 연구에서는 전기장분사(Electrostatic spraying: ES)를 사용하였다. 실험에서는 ES와 기포발생판을 비교하였는데 ES실험에서는 전압을 0 kV에서 4 kV 범위까지 높여주어 물질전달효과를 살펴보았고 기공크기가 다른 두 가지 기포발생판(미세기공: 기공크기 $10{\sim}15{\mu}m$, 중간기공: 기공크기 $40{\sim}60{\mu}m$)을 사용하여 물질전달효율을 비교 분석 하였다. 물질전달효율은 시간의 경과에 따른 용존오존농도의 측정과 페놀의 산화시간으로 간접 계산하였다. 실험 결과 ES의 경우 전압을 0 kV에서 4 kV까지 올렸을 때 기포의 크기가 작아짐으로 인해 오존전달율을 약 40% 정도 향상시킬 수 있었다. 또한 ES와 기포발생판의 물질전달 비교실험에서 미세기공 기포발생판보다 4 kV의 ES가 더 효과적임을 알 수 있었다.

• 플랜트 저널
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• 제16권1호
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• pp.34-37
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• 2020

최근 한국의 미세 먼지 오염도가 급격히 증가함에 따라 배가스 내 미세먼지를 더욱 효과적으로 집진할 수 있는 기술에 대한 관심 또한 증가하였다. 본 연구에서는 습식 전기집진기와 사이클론 집진기에 정전분무 기술을 결합하여 집진 성능의 증대를 목표로 한다. 정전분무는 일반적으로 질량분석, 혹은 반도체 코팅에 이용되므로 그 유량이 매우 적다. 분무 액적과 미세먼지의 이온결합을 통하여 집진을 해야하는 본 연구의 특성상 기존 정전분무의 유량에 대비하여 매우 큰 유량을 사용하게 된다. 따라서 기존의 정전분무 시작 전압, 혹은 분무 형상과는 다른 형상을 보일 수 있다. 본 연구에서는 기존 정전분무와는 다른 유량 및 전압 범위를 사용함으로써 예상되는 다양한 형상 특성을 살펴보고자 한다.

• Journal of Electrochemical Science and Technology
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• 제1권1호
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• pp.45-49
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• 2010

$Li_2PtO_3$ thin film electrodes, which might be possible candidate for the cathode materials for implantable batteries, were synthesized using an electrostatic spray deposition (ESD) technique onto a platinum foil substrate. Single phase $Li_2PtO_3$with a structure similar to layered $LiCoO_2$ structure were synthesized by spraying a precursor solution of $CH_3CO_2Li2H_2O$ in ethanol onto a Pt substrate at temperatures ranging from 200 to $400^{\circ}C$ followed by annealing at above $600^{\circ}C$. Lithium carbonate was the only major phase at temperatures up to $500^{\circ}C$. The X-ray diffraction (XRD) peaks of the Pt foil substrate and lithium carbonate disappeared at temperatures >$600^{\circ}C$. The volumetric capacity of the $Li_2PtO_3$ thin film synthesized using the ESD technique was approximately 817 mAh/$cm^3$, which exceeded that of $LiCoO_2$ (711 mAh/$cm^3$).

• 대한기계학회논문집B
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• 제22권8호
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• pp.1111-1120
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• 1998

Spray Drying Absorber(SDA) system, where the combustion product gas is mixed with atomized limestone-slurry droplets and then the chemical reaction of $SO_2$ with alkaline components of the liquid droplets forms sulfates, has been widely used to eliminate $SO_2$ gas from coal fired power plants and waste incinerators. Liquid atomization is necessary because it can maximize the reaction efficiency by increasing the total surface area and dispersion angle of the alkaline components. First, numerical calculations using FLUENT are carried out to investigate $SO_2$ concentration distribution and thus to calculate $SO_2$ removal efficiency. So to attain the optimized spray conditions, then an electrostatic spraying system is set up and spray visualization is performed to show the effect of an electric field on overall droplet size. Next, the effect of an electric field on the concentrations of $SO_2$ is experimentally examined. Field strength is varied from -10 kV to 10 kV and configurations of conduction charging and induction charging are utilized. Consequently, the electrostatic removal efficiency of 501 increases about 30% with the applied voltage of ${\pm}10kV$ but is independent of polarity of the applied voltage. It Is also found that the conduction charging configuration results in higher efficiency of $SO_2$ removal that the induction charging configuration. Finally, the effect of slurry temperature on $SO_2$ removal is studied. The temperature influences on the electrostatic removal efficiency of $SO_2$.

• 조명전기설비학회논문지
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• 제17권4호
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• pp.74-80
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• 2003

직류 고전압이 침 대 평판전극에 인가된 불평등전장에서 코로나방전이 발생하게 되면 하전입자들의 이동에 의한 이온풍이 발생한다. 코로나 방전현상은 오존발생장치, 전기집진장치, 정전 냉각과 도색 등의 응용분야에서 다각도로 연구되어 왔으며, 최근 이온풍은 열전달장치, 공기순환장치 등에 이용되기도 한다. 본 연구에서는 침 대 중공평판전극에 직류 고전압을 인가하였을 때 발생하는 이온풍의 속도와 풍량의 제어 특성을 분석할 목적으로 인가전압, 중공의 크기, 전극간 거리의 변동에 따른 풍속의 변화를 측정하였다. 결과로서 이온풍에 의한 기류가 침전극으로부터 평판전극을 향하는 방향으로 발생하였으며, 중공평판전극의 후면의 100~200 [mm]지점에서 측정한 이온풍의 풍속은 인가전압에 따라 1~3[㎧]의 범위에서 증가하였다.

• 한국전기전자재료학회논문지
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• 제37권1호
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• pp.79-87
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• 2024

This paper is a study on the optimal microdroplet generation conditions in indirect charging electrostatic spraying. Unlike the direct charging method, which applies power to the nozzle, the indirect charging method applies power to the discharge electrode between the nozzle and the collection electrode. Therefore, an electrically simplified system can be obtained by minimizing the insulation part a stable spray pattern can be obtained with a wide spray angle, and a stable spray pattern can be obtained with a wide spray angle. To conduct the study, an indirect charging type electrostatic spray visualization system was constructed and the static characteristics of the microdroplets were analyzed through image processing of the spray shape of the microdroplets. The total number of microdroplets and the number of microdroplets per power consumption are confirmed according to the changes in the distance between the discharge electrode and the collection electrode, the flow rate, and the applied voltage, which affect the generation of microdroplets, and using this, the optimal generation conditions are derived and the corresponding microdroplet size distribution was analyzed. As a result of the experiment, it was confirmed that the optimal generation condition was at a flow rate of 15 to 20 mL/min and a voltage of -22.5 to -25 kV in terms of the number of microdroplets, and at a flow rate of 15 to 20 mL/min and a voltage of -20 kV in terms of energy consumption efficiency.

• 한국표면공학회지
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• 제33권4호
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• pp.233-240
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• 2000

A novel electrostatic spraying method to solidify molten zinc coating layer was studied by SEM and measurement of sample's temperature. The sprayed droplets also served as nucleation sites in the solidification reaction of molten zinc but might leave the pitting mark by impinging on its surface especially at high spray pressure. Our experimental results showed that electric field could change the sprayed particle trajectories and assist the fine droplets to attach on the surface. Thus, by reducing the spray pressure and by applying the electric voltage higher than -20 KV to charge the droplets electrostatically, we could produce the spangle free galvanized coating layer without pitting.

• 한국입자에어로졸학회지
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• 제14권3호
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• pp.73-80
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• 2018

Recently, there has been much research on the effect of ultrafine dust on human body with increasing interest in the ultrafine dust. In the Republic of Korea, there are many old thermal power plants, and the amount of ultrafine dust emitted from the thermal power plants is reported to be about 14% of the total amount of domestic fine dust. Therefore, the amount of fine dust from the flue gas desulfurization facility in the thermal power plant needs be reduced. In this study, we made an experimental setup to simulate a flue gas desulfurization facility and analyzed the physical characteristics of the particles passing through a mist eliminator. Experiments were carried out to investigate the collection efficiency of the mist eliminator by using the Arizona Test Dust in a dry environment, and then spraying limestone slurry into the flue gas desulfurization system equipped with the mist eliminator to examine the size and morphology of limestone particles upstream and downstream of the mist eliminator. Cut-off size of the mist eliminator was formed at about $6{\mu}m$. The result of this study is expected to be helpful for designing an electrostatic precipitator for removing particles passing through the mist eliminator.