• Plant Journal
• /
• v.16 no.1
• /
• pp.34-37
• /
• 2020

The need to improve the performance of the dust collector by increasing the fine dust pollution in Korea is eminent. In this study, electrostatic spray wet electrostatic precipitator is used to remove Particulate Matter (PM). In order to enter the Cone-jet mode, which is the most stable spray mode among the various modes of electrostatic spraying, an appropriate voltage-flow condition must be satisfied, and a voltage-flow interval enabling this can be expressed as Stability Island. The voltage at which the conduit mode starts in the Stability Island section is referred to as the electrostatic spray minimum voltage (Onset Voltage). However, the conventional electrostatic spray is uses a very low flowrate, at most few millilitres per minute. The use of much higher flowrates has introduced different patterns of electrospray modes. In this study, the different spray modes will be studied in detail.

• Journal of Biosystems Engineering
• /
• v.21 no.4
• /
• pp.456-466
• /
• 1996

Electrostatic spraying is needed for today's sustainable farming. An electrostatic spraying nozzle was developed and its spraying performance was evaluated. High voltages of 15㎸, 20㎸, and 25㎸ were supplied for the electrostatic electrode. Artificial and real apple targets were used for the spraying experiments. Insulated material was used around the electrode to protect the loss of electrostatic effect. Three angles (0, 45, 90 degree) of spraying direction were used for the spraying test. The performance of electrostatic spraying was improved from 204.5% upto 429.2% on the apple targets.

• Journal of ILASS-Korea
• /
• v.25 no.2
• /
• pp.81-88
• /
• 2020

Electrospray is used in various industries because it can produce continuous and uniform droplets. However, it is difficult to find optimal spraying condition due to lack of data in various conditions. In this study, various conditions were divided into electric parameters and fluid property. The electric parameters set Nozzle to Substrate(NTS), nozzle diameters and the fluid property set viscosity and conductivity as conditions. In this study, it observes spray patterns, Sauter Mean Diameter(SMD) according to conditions. As a result, fluid properties had a greater effect on the cone-Jet mode than on the nozzle diameter, NTS, and flowrate. All of solutions have Stable cone-jet mode at voltage of 8.5 kV, NTS of 20 mm and nozzle diameter of 0.2 mm. SMD has 27% different depending on viscosity and conductivity. The increased flowrate and viscosity are rising break-up length and thickening jet also jet is thinned by increased conductivity. Experiments have confirmed that the jet is thickened by increased flowrate and viscosity, and that the jet is thinned by conductivity.

• Applied Chemistry for Engineering
• /
• v.19 no.1
• /
• pp.117-121
• /
• 2008

In this study, thin YSZ film was prepared by electrostatic spray deposition. The morphology of thin film was strongly influenced by precursor solution and substrate temperature. Especially, dense YSZ film was obtained at the substrate temperature of $400^{\circ}C$. The YSZ film growth rate was $12{\mu}m/h $ at the optimum conditions. Product film was characterized by XRD, FE-SEM and EDX.

• Journal of ILASS-Korea
• /
• v.27 no.1
• /
• pp.26-35
• /
• 2022

Electrospray is a method of atomizing fluid using high voltage supply and capable of generating continuous flow and coherent size of droplets. Electrical system and properties of fluids has enabled electrospray to have various spray modes. However, its studies have been confined only in Cone jet, which is more stable and easier to manipulate droplets' size than other spraying modes. Therefore, it is necessary to investigate and compare other spraying modes based on experimental parameters and physical properties of fluids. This research paper identified nine different spray modes. It was found out that Sauter Mean Diameter (SMD) is proportional to flow rate of fluids and maximum difference among spray modes was 1.7 times. On the other hand, SMD standard deviation had low variations on specific flow rates of fluids. Pulsed jet mode recorded the largest SMD standard deviation, while Spindle recorded the lowest.

• Plant Journal
• /
• v.18 no.1
• /
• pp.50-54
• /
• 2022

The demand for high-efficiency dust collectors is rapidly increasing to remove PM from exhaust gas emission facilities, such as thermal power plants, steel mills, and industrial cogeneration plants, as the Pmemission standards have been strengthened. In this study, the electrospray is adapted for existing electrosratic precipitator(EP) to remedy its shortcomings and to improve the performance. Electrospray has been mainly used for the purpose of generating very fine droplets, but fir the purpose of EP, the flow rate over 10 mL/min per nozzleis required, and a high flow rate condition of 65 to 200 times is required. The electrospray of high flow rate has a completely different spray shape from the low flow rate condition, and was visualized through various figures such as corona discharge photographs and shadow images.

• Applied Chemistry for Engineering
• /
• v.21 no.1
• /
• pp.76-80
• /
• 2010

In this study, YDC powders with uniform composition and particle size were synthesized by a citrate method and their thin film deposition was conducted by electrospray deposition method. Polymeric precursor was prepared first by reaction of metal salts with citrate acid and ethylene glycol. Fluorite crystalline YDC powders were obtained by calcining the precursor at $750^{\circ}C$ for 3 h. The electrospray deposited films prepared at the optimum conditions became dense and defect-free after heat treatment at $1400^{\circ}C$ for 3 h. The film thickness was linearly varied with the deposition time.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.25 no.11
• /
• pp.1552-1560
• /
• 2001

This paper presents the experimental results of a study undertaken to develop an electrostatic spray system for a combustion application. The characteristics of the liquid atomization and the droplet dispersion in the electrostatic spray of twin fluids were investigated by the optical measurement techniques. The processes associated with the break-up of charged jets were also observed using the laser sheet visualization. The diameter and velocity of droplets were simultaneously measured using the phase Doppler measurement technique. The electrostatic atomization of the liquid fuel depended primarily on the charging voltage and the flow rate, but the dispersion of droplets depended significantly on the aerodynamic flow. Aerodynamic influences on the liquid atomization decreased with an increase of the charging voltage. Consequently, the liquid atomization and the droplet dispersion could be independently controlled using the electrostatic and aerodynamic mechanisms.

• Particle and aerosol research
• /
• v.13 no.4
• /
• pp.151-158
• /
• 2017

Electrostatic precipitator is widely used to remove particulate matters in indoor air and industrial flue gas due to low pressure drop and high collection efficiency. However, it has a low collection efficiency for the submicrometer sized particles. Electrospraying is a potential method to increase the particle charging efficiency, which results in increased collection efficiency. Although particle charging efficiency is highly dependent upon droplet size, the effective measuring method of the droplets is still uncertain. Tap water was electrosprayed in this study, and the images of electrosprayed droplets were taken with a high speed camera coupled with several visualization methods in order to measure the droplets size. The droplet size distribution was determined by an image processing with an image-J program. As a result, a droplet measured by a laser visualization, had a half size of that by a Xenon light visualization. In addition, the experimentally measured droplet sizes were a good agreement with the predicted values suggested by $Fern{\acute{a}}ndez$ de la Mora and Loscertales(1994).

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1999.07a
• /
• pp.22-27
• /
• 1999

최근 정밀농업기술의 중요성이 인식되면서 점살포, 직접살포, 또는 방제목표물의 크기에 따른 분무량 조절 등의 기술이 개발되고 있으나 모든 기술이 분무량 조절에만 치중되어 있다. 일반적인 수압식 노즐의 경우에 분무압을 이용하여 분무량을 제어하면 분무입자의 크기가 적정 이외의 크기로 살포되어 효율적인 방제효과를 얻기가 어렵다. 하나의 제어인자 즉 분무압만을 이용하여 두 가지의 특성 즉 분무량과 분무입자의 크기를 조절하는 것은 이론적으로 불가능하다 정밀방제에 있어 분무입경과 분무량을 독립적으로 조절할 수 있으려면 두 가지 제어인자를 가진 노즐을 이용해야만 가능하며 이러한 범주에 속하는 노즐로는 원심노즐과 이류체노즐, 정전화노즐 등이 있다. (중략)