• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.04a
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• pp.131-135
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• 1997

최근 자동차에 요구되는 주요한 기술과제 중에서 최우선으로 해결해야 될 문제는 환경규제와 관련된 대응방안을 강구하는 것이다. 또한 지속적으로 강화되고 있는 환경규제를 만족하면서 소비자가 요구하는 자동차의 주행성, 안전성, 연비, 메인터난스 등과 관련된 고성능화가 추구되고 있다. 엔진유 측면에서는 배기규제, 연비향상, 장수명화 및 고성능화와 관련이 되는 성능 개선이 요구되고 있다. 특히 배기 규제와 관련해서는 오일 소모량의 감소와 배기 정화 장치에의 피독작용 감소등의 측면에서 물성이 규제되고 있는데 Noack증발 감량 및 함유량 규제가 대표적인 예이다. 본 보고에서는 제1보의 실험에 추가하여 윤활유의 혼입이 휘발유의 연소및 배기에 주는 영향에 관하여 연구하였다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.7
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• pp.905-917
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• 2021

Atmospheric pollutant emissions, mainly exhaust gas emissions from vessels, and the resultant social costs of pollution in the Korean harbor cities of Incheon, Mokpo, Gwangyang, Busan and Ulsan, are examined in this study, and the need for an emissions reduction plan is highlighted. Busan had several vessels entering its port, while Mokpo had few vessels, yet the vessels emission contribution was high in both the cities. Ulsan had world-class heavy-chemical industries, Gwangyang had steel mills and Incheon had a manufacturing industry and more vessels entering its port than Mokpo, yet the emission contribution was low in these cities. By calculating exhaust gas emissions from the vessels, it was found that CO₂ was the highest, followed by NOx and SOx. By vessel type, Busan, Ulsan, and Incheon had more oil tank vessels, Gwangyang had more cargo vessels, and Mokpo had more ferries. As a result of social cost, Busan paid the highest, while the highest emission was PM. The use of low-sulfur oil can directly reduce PM and, SOx emissions and indirectly reduce NOx emissions. However, in order to reduce high CO₂ emissions, only low-sulfur oil will not help. Therefore, the study suggested the need for reduction plan that use of fossil fuels, by using alternative maritime power (AMP).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.242-243
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• 2009

배기토출음은 공회전시 발생하는 소음에 큰 영향을 끼친다. 연비를 높이기 위하여 공회전시 RPM을 낮추면 엔진 점화 주파수가 낮아지며, 이 경우 배기계 위치에 따른 음향학적 공명 주파수와 일치하면 배기 토출음의 크기가 증가한다. 따라서 본 연구에서는 공회전시 배기토출음을 줄이기 위해 소음기의 위치와 각 배기관들의 길이를 최적화하였다. 최적화 결과로써 3 가지 배기계 위치를 얻을 수 있었고, 실제 실험과의 비교를 통하여 최적화된 배기계 위치가 그렇지 않은 배기계 위치에 비하여 소음 저감량이 높은 것을 확인하였다.

• Journal of the Korean Vacuum Society
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• v.12 no.2
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• pp.86-92
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• 2003

The pumping characteristics of a commercial UHV cryopump with a G-M refrigerator for various gases were investigated. The pumping speeds as a function of pumped amount of $H_2,\; D_2,\; He,\; Ar,\; N_2$, CO and the pumping capacity of $N_2$ were measured and the trend was theoretically analyzed. The spectrum change of the residual gas was also investigated during cyropump operation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.15-20
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• 2018

The objective of this study is to numerically investigate the thermal characteristics of an automobile exhaust-based heat exchanger for automotive thermoelectric power generation with various exhaust gas mass flow rates and temperatures. The heat exchanger for automotive thermoelectric power generation has a square-type pin installed inside, so the maximum amount of heat can be transferred to the thermoelectric element from the heat energy coming from the automobile exhaust gas. The exhaust gas mass flow rate changed from 0.01, to 0.02, to 0.03 kg/s, and the exhaust gas temperature changed from 400, to 450, to 500, to 550, to $600^{\circ}C$, respectively. A numerical simulation was conducted by using the commercial program ANSYS CFX v17.0. Consequently, the exhaust gas pressure difference between the inlet and the outlet of the heat exchanger is determined according to the flow rate of the exhaust gas. When the mass flow rate of the exhaust gas increased, the pressure difference between the inlet and the outlet of the heat exchanger increased, but the exhaust gas pressure difference between the inlet of the heat exchanger and the outlet did not vary with the exhaust gas temperature. Therefore, in order to obtain the maximum surface temperature from the heat exchanger, the exhaust gas mass flow rate should be lower, and the exhaust gas temperature should be higher.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.357-357
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• 2018

국제해사기구(IMO)에서는 황산화물(SOx)에 대한 배출 규제를 강화하고 있다. 2020년 1월 1일부터는 황함유량 0.5% 이하 선박연료유 사용을 의무화하고 있다. 그리고 온실가스 배출량 모니터링을 2019년 1월 1월부터 시행하여 총톤수 5천톤 이상 선박은 연료유 사용량을 의무적으로 보고해야 한다. 또한 배출통제구역(Emission Control Area, ECA)이 확대되고 있으며 지역별로도 저유황유 사용 의무화를 도입하는 항만이 증가하고 있다. 이와 같이 항만구역에서 선박 배기가스 배출 규제를 강화하고 있다. 본 연구에서는 컨테이너 물동량이 증가하고 있는 서산 대산항 컨테이너 부두를 중심으로 항만구역에서 배출되는 배기가스를 산출하였다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.1
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• pp.40-49
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• 2000

The flow and heat transfer characteristics of the exhaust airflow window system were studied numerically by a finite volume method. Attention was paid to see the decrease in indoor cooling load. The exhaust air flow rate, solar energy power and aspect ratio of window were considered as main variables. From the result of the comparison between the exhaust airflow window and the enclosed window, the indoor heat gain was reduced remarkably by 76%. It is also suggested that in the design of the exhaust airflow window optimum values of aspect ratio, H/W and exhaust air flow rate, Re were about 0.05 and 600, respectively.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.6
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• pp.639-647
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• 2014

Due to global warming and depletion of fossil fuels, technologies reducing $CO_2$ emission and increasing fuel efficiency simultaneously are required. An exhaust gas heat recovery system is a technology to satisfy both issues. This study analyses three types of heat exchanger installed on an exhaust pipe. In case of plate type heat exchanger, back pressure rapidly increased and maximum cylinder pressure reduced in high speed and maximum load, and back pressure increased over twice and specific fuel consumption also increased up to 2% which were the highest increasing rate. In case of fin tube type, the amounts of exhaust emissions and specific fuel consumption rate were less than the other two types. The effect of shell and tube was in the middle. Making a decision by only the effect on engine performance, a fin tube type is the best for exhaust heat recovery systems.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2002.11a
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• pp.39-44
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• 2002

배기가스의 규제가 전 세계적으로 강화되고 있는 가운데, 경유사용 디젤기관은 가솔린기관 보다 열효율이 높고 온실가스인 $CO_2$ 배출량이 적은 장점이 있으나, PM(입자상 물질)과 NO$_{x}$가 다량 배출되는 단점이 있다. 이들의 저감책으로서, 엔진개량, 연료분사장치의 고압화와 전자제어화, 배기 후처리기술의 적용 등 디젤기관의 고효율성을 손상시키지 않으면서, 배기공해를 대폭 저감하려는 연구가 활발히 추진되고 있으며, 한편으로는 디젤기관의 대체연료에 대한 연구가 활발히 추진되고 있다.(중략)

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.32 no.11
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• pp.63-68
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• 2003

주방환기의 계획에 있어서 조리시 발생하는 오염물질을 적절히 배기시키는 것이 가장 중요하다. 기구의 배치와 발열량을 평가하고 후드의 위치와 종류 그리고 덕트직경과 경로를 결정하며 적정한 풍량을 제거하기 위한 배기팬을 선정한다. 그러나 일반적인 실내 공기밸런스 계획을 시행함에도 불구하고 배기된 체적에 해당하는 풍량을 보충 공급하는 방식에 대한 고려는 현재 상대적으로 부족한 상태이다.