• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.100-101
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• 2018

Environmental problems caused by air pollution have been considered as serious critical issues in global perspectives. Controlling greenhouse gases has become one of the major environmental problems in construction fields as well. However, similar studies were mainly focused on suggestion of various methodologies for measuring CO₂ emissions of construction equipment and calculating emissions. This study aims to analyze the correlation between the CO₂ emissions and RPMs of equipment by the construction process based on row data collected from construction equipment actually operated in job sites. This study allows site personnels to determine the amount of emitted CO₂ under particular construction equipment under specific conditions during the targeted construction operations. The research findings expect to be used as fundamental informations for establishing environment-friendly construction operation planning.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.6
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• pp.95-100
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• 2005

Since air pollution has become a globally critical issue and exhaust emissions from automobiles cause a major source of air pollution, many countries including advanced countries have stipulated stringent emission regulations. This research focused on engine performance characteristics with the application of a continuous regeneration diesel particulate filter and EGR together in a heavy duty vehicle, and gives some suggestions on the direction of designing points of view by comparing the experimental data with numerical results which were obtained through KIVA-3V.

• Journal of the Korean Society of Combustion
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• v.22 no.1
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• pp.23-31
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• 2017

Large-scale fuel tanks emit massive amount of hardly-combustible VOC mixtures which are light hydrocarbon species in dilution with nitrogen and carbon dioxide. We have developed a lab-scale burner to combust those VOC mixtures by use of a turbulent partially-premixed flame as a pilot flame. For a higher HC treatment ratio, the mixture gases were reformed by a rotating arc plasma device. The results showed that the nitrogen mole fraction and the injecting speed of the VOC mixture influence on the performance of the burner. It was also found that the size of the pilot flame and the power supplied to the plasma device determine the overall HC treatment ratio and the concentrations of CO and NOx in the exhaust gas.

• 한국연소학회:학술대회논문집
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• 2013.06a
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• pp.37-40
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• 2013

Hydrogen-dimethy ether (DME) and hydrogen-diesel compression ignition engine combustion were investigated and compared each other in a single cylinder compression ignition engine. Hydrogen and DME were used as low carbon alternative fuels to reduce green house gases and pollutant. Hydrogen was injected at the intake manifold with an injection pressure of 0.5 MPa at fixed injection timing, $-210^{\circ}CA$ aTDC. DME and diesel were injected directly into the cylinder through the common-rail injection system at injection pressure of 30 MPa. DME and diesel inejction timing was varied to find the optimum CI combustion to reduce CO, HC and NOx emissions. When DME was injected early, CO and HC emissions were high while NOx emission was low. Fuel consumption, heat release rate, and exhaust emissions were measured to analyze each combustion characteristics of each ignition promoter. Fuel consumption was decreased when diesel was used as an ignition promoter. This is due to the lower volatility of diesel which created more stratified charge than DME.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.252-258
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• 1998

In a SI engine, it is necessary to control fuel quantity in accordance with intake air amount in order to reduce exhaust emission and improve the specific fuel consumption. Generally the map data is used for the vehicles with a SI engine. For the precise control of air-fuel ratio, the real time control method is recommended rather than the control method using map data. In this paper, we developed real time control system using microprocessor and IBM-PC, and applied it to the commercial SI engine. We got good results for air-fuel ratio under the idle condition.

• Journal of the korean Society of Automotive Engineers
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• v.2 no.2
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• pp.31-39
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• 1980

복지사회적 목표에서의 도시계획 및 교통문제는 환경보전의 측면에서 상충되는 관계가 이루어 지고 있다. 특히 대도시에서 자동차의 배출가스에 의한 대기오염은 매우 심각한 관계에 이르고 있다. 우리나라에서도 앞으로 급증할 것으로 예상되는 자동차 증가율과 상대적으로 협조한 도 로의 점유율 및 이에 따른 자동차 주행 pattern의 불규칙성을 감안하면 외국과 같은 규제기준의 설정이 필요하다. 자동차 배출가스에 의한 대기오염의 심각성은 배출가스중에 들어있는, 일산 화탄소(CO), 탄화수소(HC), 질소산화물(NOx), 알데히드, 연화합물 및 발암성 방향족화합물 등 으로, 이것은 인체에 유해한 영향을 주고 있다. 이와 같은 실정에서 인간의 건강을 공해로부터 보호하기 위한 기준으로 세계보건기구 WHO 는 1972년 "WHO Technical Report Series, No.506" 에서 SO$_{2}$ 분진 일산화탄소 및 photochemical 에 대하여 기준 목표를 설치하였다.목표를 설치하였다.

• Journal of Power System Engineering
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• v.9 no.3
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• pp.26-32
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• 2005

The volumetric efficiency is significantly affected by the behavior of pressure wave in induction system and exhaust pipe. By the motion of the piston, there exist pressure fluctuation in induction system which produce waves. Waves are propagated along a pipe bi-directional as they propagated through it, making compression wave and rare-faction(expansion) wave. These wave phenomena can affect to the volumetric efficiency. As a method of improvement of the volumetric efficiency, fuel economy and pollutant emission reduction particularly in low engine speeds, a side-branch additional tunable helmholtz resonator on the secondary pipe of intake system is proposed by use of their acoustic vibrations. Some of results are presented which deal with their physical phenomena for the wave action of intake system in a four-stroke three cylinders diesel engine.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.4
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• pp.809-816
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• 2001

This is a fundamental study to improve the performance of the LPG engine. The result were summarized as followed. 1. The measured torque and power on the fuel of LPG were indicated about 8% lower than those on gasoline with the same compression ratio. 2. In the case of LPG, BSFD at compression ratio of 9.7 was about 5% lower than that of 8.3 at 3,000ppm 3. HC and CO concentrations of the LPG were lower about 53%, 35% than those of gasoline

• Journal of Mechanical Science and Technology
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• v.19 no.12
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• pp.2321-2329
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• 2005

One means of fulfilling $CO_2$ emission legislation is to downsize engines by boosting their power using turbochargers or mechanical superchargers. This reduces fuel consumption by decreasing the engine displacement. When a turbocharger, which is preferable to a mechanical supercharger in terms of fuel efficiency, is used, there is insufficient availability of exhaust gas energy at low engine speeds, resulting in an unfavorable engine response. Therefore, mechanically driven superchargers have increased in popularity due to their quick response to changing speeds in the transient phase. However, since a mechanical supercharger obtains its driving power from the engine, it is difficult to decrease its fuel consumption. This remains a large negative factor for superchargers, despite their excellent dynamic performance. This study aims to develop a power control concept to improve the fuel economy of a mechanical screw supercharger, which could then be used for engine downsizing.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.389-395
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• 2000

It is usually the contractual responsibility of HRSG(Heat Recovery Steam Generator) supplier to limit combustion turbine exhaust noise at cogeneration sites. Thus, it is necessary to predict the noise level from HRSG at the stage of preliminary design. HRSG is usually composed of inlet duct, main casing, outlet duct, stack. To satisfy the noise limit level, additional equipments are sometimes required - duct shroud, silencer. We develop algorithms for predicting the noise emission from all these equipments of HRSG units. For the convenience of user, we develop the GUI window version program, named NP-HRSG program. To evaluate the accuracy of this program, predicted noise levels from a real HRSG model are compared with measured data. Through this comparison, we observe that the maximum error is just about 3dB.