• Transactions of the Korean hydrogen and new energy society
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• v.27 no.5
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• pp.485-493
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• 2016

Recently submarine and unmanned underwater vehicle (UUV) are equipped with a fuel cell system as an air independent propulsion system. Methanol fuel processor can efficiently supply the hydrogen to the fuel cell system to improve the ability to dive. This study investigated the optimal conditions of the methanol fuel processor that may be used in the closed environment. For this purpose, the numerical model based on Gibbs minimization equation was established for steam reformer and three exhaust gas burners. After simulating the characteristics of steam reformer according to the steam-to-carbon ratio (SCR) and the pressure change, the SCR condition was able to narrow down to 1.1 to 1.5. Considering water consumption and the amount of heat recovered from three burners, the optimum condition of the SCR can be determined to be 1.5. Nevertheless, the additional heat supply is required to satisfy the heat balance of the methanol fuel processor in the SCR=1.5. In other to obtain additional amount of heat, the combustion of methanol is better than the increased of SCR in terms of system design.

• Journal of Energy Engineering
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• v.23 no.2
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• pp.57-61
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• 2014

Challenges the automotive industry as the increase in consumption of oil and energy, $CO_2$ emissions of global warming, caused by exhaust emissions and urban air pollution, it is time for a deal is needed. The solution of these highly regarded in the market as there is a demand of electric cars. In this study, electric car motor, battery and high-voltage core components, including the drive motor of the effective thermal management technologies, thermal management of the battery and the drive motor to evaluate the technology and development trends.

• Environmental Analysis Health and Toxicology
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• v.17 no.3
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• pp.207-217
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• 2002

This study was designed to investigate the characteristics of atmospheric concentrations of toxic volatile organic compounds (VOCs) in Korea. Target compounds included 1,3-butadiene, aromatics such as BTEX, and a number of carbonyl compounds. In this paper, as the second part of the study, the seasonal and locational concentrations of atmospheric VOCs were evaluated. Sampling was conducted seasonally at seven sampling sites. each of them representing a large urban area (commercial and residential), a small urban area (commercial and residential), an industrial area (a site within the complex and a residential), and a background place in Korea. In general, higher concentrations were found in the petro-chemical industrial site than other sites, while VOCs measured in commercial (heavy -traffic) sites were higher than residential sites. Seasonality of VOCs concentrations were not so much clear as other combustion related pollutants such as sulfur dioxide, indicating that the VOCs are emitted from a variety of sources, not only vehicle exhaust and point sources but fugitive emissions. Except the industrial site, the concentrations of VOCs measured in this study do not reveal any serious pollution status, since the levels did not exceed any existing ambient standards in the U.K. and/or Japan. However, the increasing number of petrol -powered vehicles and the rapid industrialization in Korea may result in the increased levels of VOCs concentrations in many large urban areas in the near future, if there is no appropriate programme implemented for the control of these compounds.

• Journal of the Korean Society of Safety
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• v.22 no.6
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• pp.13-19
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• 2007

Diesel car's smoke measurement equipment and method were investigated based on the exhaust gas regulations. Reflection photo method and light extinction method for measuring smoke were compared under conditions of both no load mode and Lug-down 3 mode. Free acceleration mode at no load condition was used for regular inspection of diesel car, and Lug-down 3 mode was used for fine inspection of the diesel car. A correlation between no load mode and Lug-down 3 mode was investigated in this research. The smoke measured with reflection photo method was 1.5${\sim}$2 times higher than that of light extinction method The correlation coefficient between reflection photo method and light extinction method for measuring smoke was 0.83, which shows comparatively high correlation between the two methods for measuring smoke in diesel engines.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.13-19
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• 2013

This study examines thermal safety on three-way catalyst that dominates 70% among whole exhaust gas purification device in 2003. Three-way catalyst maintains high temperature in interior domain but maintains low temperature on outside surface. Therefore this device shows tensile stress on outside surface. Temperature distribution of three-way catalyst was acquired by thermal flow analysis for predicted thermal flow parameter. Thermal stress analysis for three-way catalysis was performed based on this temperature distribution. Thermal safety of three-way catalyst was estimated by strength reduction factor and failure probability.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.137-143
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• 2014

Car exhaust emissions are recognized as one of the key sources for climate change and electric vehicles have no emissions from tailpipe. However, the limited charging infrastructures could restrict the propagation of electric vehicles. The purpose of this study is to find the vulnerable districts limited to the charging station services after meeting the goal of Ministry of Knowledge Economy(12%). We assumed that the charging service can be provided by current gas stations. The range of the vulnerable grades was determined by the accessibility to current gas stations and the vulnerable regions were classified considering the optimal number of charging stations estimated by the efficiency function. We used 4,827 sub-municipal divisions and 11,677 gas station locations for this analysis. The results show that most of mountain areas are vulnerable and the fringe areas of large cities generally get a good grade for the charging infrastructure. The gangwon-do, jeollanam-do, gyeongsangbuk-do, and chungcheongnam-do include more than 40% vulnerable districts.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.3 s.120
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• pp.274-281
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• 2007

Road traffic noise is not produced by any one factor rather it occurs as a composition of various factors. Its occurrence is made by running engine noise, tire frictional, and exhaust noise etc. The quality of the noise depends on the size of the vehicles, rotation and engine speed, vehicle load, package state of the road and incline etc. The occurrence of any noise level of heavy trucks appears louder than smaller vehicles and the noise levels produced differs according to speed and load etc between similar size vehicles. Other factors such as traffic density, average speed, mixing rate of heavy vehicles, and the distance between vehicles also generate road traffic noise. In this paper we examine 2, 4, and 6-lane roads in Jeonju. Consequently, this study examines the means used to measure road traffic noise. It was found that when there is a large traffic density and the average velocity is below 70 km/h, the noise level could receive a relative proper value by the current measuring means. But in the case of night-time, it was found that the current measuring method is inapposite.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.172-173
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• 2019

As the damage to fine dust increased, the Republic of Korea designated fine dust as a social disaster. The composition of the fine dust is composed of carbon, sulfate, nitrate, ammonium and minerals. The cause of fine dust is naturally generated by dirt, pollen, etc. In addition, there are artificial causes such as gaseous vehicle exhaust gas emitted from the use of fossil fuel. When fine dust enters the human body through breathing, it causes various respiratory diseases and skin diseases. In IARC, fine dust was designated as a carcinogen group 1. In this research, we tried to adsorb fine dust by physical adsorption using powdered activate carbon. Powdered activate carbon is a powdered activated carbon activated in a carbonized state. Porous material with high specific surface area and low density. Experimental items were tested for density, water absorption, and fine dust concentration according to the PAC addition ratio. Basic experiments were carried out to fabricate the fine dust adsorption matrix.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.3
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• pp.47-52
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• 2021

Fine dust generated from vehicle brakes accounts for a significant amount of fine dust from non-exhaust system. Since such brake fine dust contains a large number of heavy metal components that are fatal to the human body, a device capable of collecting them needs to be developed. A mini cyclone, one of the devices that can effectively collect fine dust, has the advantage of relatively simple shape and high collection efficiency. Therefore, in this study, the collection efficiency of the mini-cyclone was numerically analyzed using CFD in order to find out whether such a mini-cyclone is suitable for collecting brake fine dust. As a result, the cut-off diameter was predicted to be about 1.5㎛, which means that the particle trapping load of the filter can be drastically reduced. Therefore, there is a possibility that the mini-cyclone can be used to collect fine dust from disc brakes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.37-45
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• 2018

An electric vehicle is an environmentally friendly vehicle because there is no exhaust gas, unlike gasoline automobiles. On the other hand, because the electric vehicle is driven by electric power charged in batteries, the distance to go through a single charge depends on the energy density of the batteries. Therefore, a lithium-ion battery with a high energy density is a good candidate for batteries in electric vehicles. Because the electrode is an essential component that governs the efficiency of a lithium-ion battery, the electrode manufacturing process plays a vital role in the entire production process of lithium-ion batteries. In particular, the drying process during the electrode manufacturing process is a critical process that has a significant influence on the performance. This paper proposes an innovative process for improving the efficiency and productivity of the drying process in electrode manufacturing and describe the equipment design method and development results. In particular, the design procedure and development method for enhancing the electrode adhesion power, atmospheric pressure superheated steam drying technology, and drying furnace slimming technologies are presented. As a result, high-speed drying technology was developed for battery electrodes through the world's first turbo dryer technology for mass production using open/integrated atmospheric pressure superheated steam. Compared to the conventional drying process, the drying furnace improved the productivity (Dry Lead Time $0.7min{\rightarrow}0.5min$).