• Transactions of the Korean Society of Automotive Engineers
• /
• v.9 no.1
• /
• pp.102-111
• /
• 2001

To describe the air flow characteristics within an air cleaner cover and mass air flow sensor (MAFS) entry region installed in a 3.0L engine air induction system, flow visualization, velocity and turbulence intensity measurements were taken in several view planes. A detailed knowledge of the interaction between the design parameters and the flow structures will enhance our understanding of the motions within the flow field and enable engineers to optimize the induction system and reduce the signal-to-noise ratio in the MAFS output. Emphasis is placed on the analysis of coherent motions and the controlling parameters which affect the air flow in the MAFS entrance region over a flow rate of 13-240 kg/hr. The high speed motion pictures illustrated that the air flow generated within the air cleaner cover under steady state condition is quite complex. In both axial and radial planes of the main passage it was found that the flow pattern is remarkably influenced by the air cleaner cover and main passage configuration. A comparison of the flow patterns and measurements in the original and modified air cleaner cover is presented. Measurements from the MAFS indicated an significant reduction in pressure drop and signal noise for the modified cover as compared with the original cover, over an air flow rate of 13-240 kg/hr.

• Journal of Environmental Health Sciences
• /
• v.33 no.4
• /
• pp.250-254
• /
• 2007

The reduction efficiency of air cleaner on particulate contaminants such as dust, airborne bacteria and fungi distributed in the office was relatively higher in case of office with workers than office without workers. This result would be attributed to workers' activities and physical characteristics of particulate contaminants. The air cleaner decreased a concentration of airborne bacteria more than airborne fungi, which implicates that difference of dust adsorption between airborne bacteria and fungi would affect an operation efficiency of air cleaner.

• Proceedings of the Korean Environmental Health Society Conference
• /
• 2003.06a
• /
• pp.181-182
• /
• 2003

Our study from Feburary to March, 2003, were done in university office A and B, located in Seoul. This study was carried out to investigate the reduction of the airborne fungi before and after we activate the air cleaner which using ionization. And the method of assessment was done by the CAMNEA method. The result was as follows. 1. In the research office A, the concentration of the airborne fungi was 18(${\pm}$11.3) CFU/㎥ before the ionizing air cleaner system was turned on: whereas three days after this result the concentration decreased to less than 1 CFU/㎥. 2. In the laboratory office B, the concentration was 210.6(${\pm}$5.3) CFU/㎥ before using the air cleaner and was decreased to 32.2(t 10.3) CFU/㎥ after using the air cleaner. The remediation rate in the experiment was 85 percentile,

• Journal of Environmental Health Sciences
• /
• v.30 no.3
• /
• pp.221-229
• /
• 2004

We estimated decreasing rate of indoor air pollutants which are PM10 and $NO_2$ by the air cleaner in indoor environment. This study respectively examined concentration of PM10 and $NO_2$ two times in 34 sites located in Seoul and Kyung-gi Do from April to September in 2003. Sectional period was respectively divided for operating the air cleaner and non-operating the air cleaner. Moreover, questionnaire was executed to grasp physical characteristic of objective building and residential characteristic of residents by using method of self-entry. There was a trend that concentration of PM10 and $NO_2$ separated number of residents during operating period respectively decreased among indoor air. According to the existence of smoker in indoor, both concentration of PM10 and $NO_2$ during operating period decreased in each case, and according to existence of pets, both cases decreased concentration of pollutants by operating the air cleaner. We used Monte-Calro simulation to remove uncertainty and identify efficiency of eliminated pollutants such as PM10 and $NO_2$ by the air cleaner. Average efficiency of removal for PM10 and $NO_2$ were 61.84${\pm}$23.04% and 48.67${\pm}$18.03% respectively.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.5 no.3
• /
• pp.47-53
• /
• 1997

The importance of intake system can not be overstressed in the recent heavy duty commercial vehicle design. The basic requirements of intake system are to have less flow resistance and better air cleaning performance which have direct effects on the performance and service life of engine. In order to improve the performance of engine intake system, the flow phenomena in the intake system should be fully understood. With readily availble CFD code, the numerical analysis becomes the more reliable tools for flow optimization in recent design work. In this research, flow field in the intake system was analyzed by STAR-CD, the 3-D computational fluid dynamics code. Especially, the flow inside of air cleaner was thoroughly analyzed. Pressure distribution and velocity profile in the air cleaner and intake duct was obtained. Having the dust seperated from incoming air at the expense of less pressure drop is the ultimate goal for the research.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.52 no.3
• /
• pp.19-29
• /
• 2010

In South Korea, as the living standard has been getting higher, meat consumption is steadily increasing. To meet the country's demand, livestock houses become larger and wider with increased raising density. In larger livestock houses, pollutants such as flake of pig skin, excrement, odor, various dusts and noxious gas like ammonia are excessively accumulated inside the facility. These will cause weak immunity for the pigs, diminution of productivity and degeneration of working condition. These problems can be solved through the ventilation performance of the facility. In the winter time, ventilation must be controlled to minimum to maintain a suitable thermal condition. However, this affects the other internal environmental condition because of the minimum ventilation. The installation of "wet air cleaner" especially in the winter time can be an alternative solution. For efficient application of this machine, there is a need to understand the existing ventilation condition and analyze the interaction of existing ventilation system with the wet air cleaner considering its appropriate location. In this study, the existing ventilation system as well as the internal environmental condition negatively inside the facility with the wet air cleaner has been studied using CFD technology. The CFD simulation model was validated from the study conducted by Seo et al. (2008). Results show that the elimination rate of ammonia was 39.4 % and stability could be improved to 35.1 % (Comparing case 5 to 1 where wet air cleaner machine was not used). It can therefore be concluded that case 5 shows the optimum location of a wet air cleaner in the livestock house.

• Journal of Environmental Science International
• /
• v.14 no.5
• /
• pp.491-497
• /
• 2005

In this study, we investigated $PM_{10},\;NO_2$, and l-hydroxypyrene(1-OHP) in urine at indoor environments which are 35 houses and 20 hospitals for using air cleaner and non-using air cleaner in Seoul metropolitan area and Kyoung-gi province from April, 2003 to February, 2004. Moreover, we examined effect of improvement for indoor air quality and health effect by concentration of 1-OHP also we investigated removal efficiency by air cleaner for $PM_{10},\;NO_2$, and 1-OHP that were 28.5\%,\;27.4\%,\;and\;42.1\%$ respectively. Concentration of$PM_{10},\;NO_2$, and 1-OHP were $19.02\pm18.14{\mu}g/m^3,\;8.66\pm3.06ppb,\;and\;0.19\pm0.18{\mu}g/g$, creatinine when air cleaner was no worked. The concentration for $PM_{10},\;NO_2$. and 1-OHP were $13.60\pm10.79{\mu}g/m^3,\; 6.29\pm2.71ppb,\;and\;0.11\pm0.10{\mu}g/g$ creatinine, respectively. It was significant statistically. Therefore, it is considered using the air cleaner to remove the partial pollutants in indoor environment and is positive effect for health.

• Particle and aerosol research
• /
• v.14 no.1
• /
• pp.9-16
• /
• 2018

We have developed an electrostatic precipitation (ESP) type air cleaner for indoor air quality and investigated its performances regarding CADR (Clean air delivery rate), single-pass efficiency and gas removal efficiency. The ESP air cleaner used an ACF (Activated carbon fiber) filter for gas removal and the ACF as a high voltage electrode for particle removal. The ESP air cleaner was tested in a chamber with the volume of $1m^3$ regarding CADR and gas removal efficiency. The applied CADR area of the ESP was $1.8m^2$. Gas removal efficiency was tested with 3 gases (Acetaldehyde, Acetic acid, Ammonia). As the results of the gas removal efficiency, the ESP air cleaner shows the removal efficiencies of 90, 98 and 85% for acetaldehyde, acetic acid and ammonia, respectively.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.142-149
• /
• 2011

The basic of installing smart air cleaner in railway system is improvement of continuous real time sensing technologies. And building smart air cleaner in railway system with IT is needed. When smart air cleaner in railway system is developed, the installation of sensor which is for measuring air quality in the passenger room and setting revolution cycle of filter which is for removing fine dust is very important. In order to install it in a train which is now running, after making of standard test certification and verification of product's stability with enough self-test, application test will be performed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.05a
• /
• pp.931-936
• /
• 2004

In this paper, vibration endurance test is carried out on rubber insulators used fur vehicle air cleaners. Based on the test results, endurance characteristics depending on type and material of the insulators are estimated. Frequency response characteristics of the air cleaner system are investigated to identify the cause of wear and failure in the insulators occurred during the endurance test. New insulator models with improved endurance characteristics are proposed by changing the frequency response property of the air cleaner system.