• Journal of the Korean Society for Precision Engineering
• /
• v.14 no.1
• /
• pp.84-89
• /
• 1997

Recentely, a compact and small size air-cleaning Electrostatic Precipitator(ESP) is needed to develop for air conditioning devices. From Deutsch formula for ESP efficiency, collection efficiency is affected not only the structure of collection section but also the charge rate of dust. In terms of collection area, the most useful type is a scroll type ESP. In this work, we investigated experimentally aptimum design factor of scroll type ESP by application of Taguchi method. And we developed the scroll type ESP by using optimal condition of control factor.

• 한국전산유체공학회:학술대회논문집
• /
• 2010.05a
• /
• pp.103-108
• /
• 2010

This article presents computational fluid dynamics (CFD) simulations of nanoparticle movements and flow characteristics in laboratory-scale electrostatic precipitator (ESP) without corona discharge, and for simulation, it uses the commercial CFD program(CFD-ACE) including electrostatic theory and Lagrangian-based equation for nanoparticle movement. For validation of CFD results, a simple cylindrical type of ESP is simulated and numerical prediction shows fairly good agreement with the analytical solution. In particular, the present study investigates the effect of particle diameter, inlet flow rate, and applied electric potential on particle collection efficiency and compares the numerical prediction with the experimental data, showing good agreement. It is found that the particle collection efficiency decreases with increasing inlet flow rate because the particle detention time becomes shorter, whereas it decreases with the increase in nanoparticle diameter and with the decrease of applied electric voltage resulting from smaller terminal electrostatic velocity.

• Particle and aerosol research
• /
• v.19 no.3
• /
• pp.89-100
• /
• 2023

In our previous study, a wire-plate type electrostatic precipitator (ESP) was developed to collect bioaerosols of 100 nm size. In the study, various flow rates (40 ~ 100 L/min) and applied voltages (3 ~ 10 kV) were tested for experiment. In this study, numerical analysis was performed for the ESP of the previous study with the same flow rates and applied voltages, but with varying the size of bioaerosols to 0.04 ~ 2.5 ㎛. Overall, the numerical analysis results well predicted the experimental data. Bioaerosols of 0.1 ~ 0.5 ㎛ showed the minimum collection efficiency for all conditions because of low charge number. The effect of the ionic wind generated by the corona discharge was calculated. However, the ionic wind did not affect much the collection efficiency. The aerosol collection in the ESP of this study was due to the electrostatic force generated by particle charge in the electric field. This numerical study on the ESP can be used for the design and optimization of higher flow rate (> 100 L/min) ESP.

• Journal of Advanced Marine Engineering and Technology
• /
• v.31 no.8
• /
• pp.904-910
• /
• 2007

In this study an experimental research has been conducted to reduce NOx and smoke emission from diesel engine exhaust gas simultaneously by application of corona discharge type electrostatic precipitator(ESP). The ESP was installed between exhaust gas silencer and outlet terminal of exhaust gas system. The operating conditions as input parameters taken in this experiment were corona power input, gas velocity and equivalence ratio of gas. It was found that the corona discharge type ESP has notable effect on reducing smoke in exhaust gas but appeared to bring slight effect on reducing NOx.

• Clean Technology
• /
• v.25 no.2
• /
• pp.147-152
• /
• 2019

Electrostatic precipitator that shows a good performance for the removal of particulate matter is important for controlling emissions from industrial facilities and power plants. The efficiency of the electrostatic precipitator on the removal of particulate matter is highly affected by the flow pattern inside the electrostatic precipitator. A number of studies have been conducted to obtain uniform flow distribution inside electrostatic precipitators. An electrostatic precipitator (ESP) with a length of 3.5 m and a height of 0.875 m was designed and installed in this study. The ESP included an inlet duct, diffuser, body, and contractor. Three perforated plates were installed in the diffuser of the ESP. Five pitot tubes were installed vertically and used to measure flow distribution in the cross section of the ESP body. Root mean square deviation value (RMS%) was used to examine the flow distribution inside the ESP when the perforated plates were installed in the diffuser. Flow distribution was also investigated in relation to the porosity of the perforated plate. The results showed that the perforated plates improved greatly the flow distribution inside the electrostatic precipitator. In addition, the most uniform flow distribution was found with 40%, 50%, and 50% porous perforated plates located from the inlet of the diffuser.

• 연구논문집
• /
• s.34
• /
• pp.21-28
• /
• 2004

In this study, we report an investigation for the charging and collection of aerosol nanoparticles in an electrostatic precipitator (ESP) according to particle charging and diffusion effects. The competition between charging probability and diffusion effect determines the collection efficiency of nanoparticles in the ESP. In conclusion, collection efficiency continuously decreased with the reduction in the particle size. This indicates that poor partial charging effect of nanoparticles is more dominant than their diffusion effect in the ESP for the nanoparticles in the particle size range of 4-20 nm. Theoretical calculations using a unipolar diffusion charing theory were in good agreement with the experimental data for the nanoparticles less than 20 nm in diameter.

• Journal of Magnetics
• /
• v.17 no.1
• /
• pp.61-67
• /
• 2012

The miniaturization of an electrostatic precipitator has become a key element in successfully constructing an efficient electrostatic precipitator because of the limited space allowed for installation in a subway tunnel. Therefore, the miniaturization of the rapping system of the electrostatic precipitator has also become important. This research proposes a resonant-type electromagnetic vibration exciter as a vibrating rapper for an electrostatic precipitator. The compact vibrating rapper removes collected dust from the collecting plates without direct impact on those collecting plates. To characterize the dynamic performance of the electromagnetic vibration exciter, finite element analysis was performed using a commercial electromagnetic analysis program, MAXEWLL. Moreover, we analyzed the resonant frequency of an electrostatic precipitator, to which the electromagnetic vibration exciter was applied, by ANSYS. Also, to measure the acceleration generated by the electromagnetic vibration exciter, we manufactured a prototype of the ESP and electromagnetic vibration exciter and measured its acceleration at the resonant frequency.

• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.34 no.12
• /
• pp.73-82
• /
• 2018

The objective of this study was to evaluate particle collection performance of electrostatic precipitator (ESP) integrated with double skin façade in naturally ventilated residential buildings using numerical method. To evaluate the efficiency, computational fluid dynamics (CFD) simulation based on electric potential and Lagrangian method was applied. The CFD model was validated by comparing the simulated results with the experimental data including thermal characteristic of double skin façade (DSF) and particle removal characteristic of electrostatic precipitator. The validation results showed that the root mean square error (RMSE) between predicted values and measured values of velocity and temperature in intermediate space of DSF was 1.2%. The adequacy of ion space charge density and turbulent model were determined. The RMSE between predicted values and measured values of collection efficiency of ESP was 9.2%. In addition, the case study was performed to present the application of the numerical method based on validation results of ESP integrated with façade.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.10
• /
• pp.1622-1628
• /
• 2007

We characterized the efficacy of an electrostatic precipitator (ESP) air-cleaner in reducing the concentration of Serratia marcescens in an enclosed space. We used an experimental room ($4.5{\times}3{\times}2.9\;m$) in which electrostatic air-cleaners were located. Two air-cleaners enhanced the equivalent ventilation rates in the chamber by about 3.3 air changes per hour (ACH) over the 2 ACH provided by the mechanical ventilation system. Natural die-off of the organisms provided an additional equivalent of 3 ACH, so that the total ventilation rate with the ESP air-ccleaners was 8.3 ACH. We also examined whether the ESP air-cleaners altered the deposition of Serratia marcescens aerosols on the experimental room surfaces. We did not find any significant differences in the number of colony forming units recovered from surfaces with and without the air-cleaners. We installed UV lights inside the ESPs and determined if UV light, in addition to electrical fields, increased the efficacy of the ESPs. The presence of UV light inside the ESP reduced S. marcescens aerosols by approximately 2 ACH. Finally, a box model indicates that the efficiency of the air-cleaner increases for both biological and nonbiological particles at ventilation rates of 0.2-1, which are typical for residential settings.

• Journal of the Korean Society of Visualization
• /
• v.20 no.3
• /
• pp.86-93
• /
• 2022

An electrostatic precipitator (ESP) is an industrial post processing facility for high efficiency dust mitigation. Uniformity of the flow passing through the inlet duct leading into the main chamber is important for efficient reduction of dust. To examine flow uniformity, this study conducted a numerical analysis of the flow within a scale-down ESP inlet duct. Magnetic resonance velocimetry (MRV) results from a prior study were utilized to validate the Reynolds-averaged Navier-Stokes (RANS) numerical simulations. Both the experimental and computational results displayed a similar recirculation zone shape and normalized velocity profile near the duct outlet for the baseline geometry. To optimize the uniformity of the flow, the number of guide vanes was modified, and the guide vanes were partially extended straight upward. Design evaluation is done based on the outlet velocity distribution and mass flowrate balance between the two outlets. Simulation results indicate that the vane extension is critical for flow optimization in curved ESP ducts.