가솔린 엔진의 공회전 천이구간에서 엔진 제어변수가 배기가스온도 및 배기배출물에 미치는 영향

정대철(Dae-Chul Jeong),박영준(Young-Joon Park),김득상(Duk-Sang Kim),조용석(Yong-Seok Cho) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

Increase of an exhaust gas temperature is important strategy which reduces a light off time of three way catalyst at the early stage of the cold start in SI engines. A proper control of engine variables is an effective way to improve emission performance in these cold start operations. This study tried to increase exhaust gas temperature through the controls of engine operating conditions such as spark timing or valve overlap when catalyst heating function is activated. Experiments showed that retarded spark timing and increased valve overlap by virtue of VVT may be helpful to increase exhaust gas temperature. It was also found that the decrease of NOx emission was expected during maintaining combustion stability of the engine with increased valve overlap. This study also showed that sudden changes in ISA and amount of fuel due to the deactivation of catalyst heating function may cause temporal increase of harmful emissions.

직접분사식 디젤기관에서 메탄올 혼합연료의 배기 배출물에 관한 연구

서정주,왕우경,김상암 여수대학교 2001 論文集 Vol.16 No.-

In this study, the fuel injection system of a DI diesel engine was modified slightly with installing two agitators and a F.O supply pump to use the methanol-blended fuel. The emission concentrations were compared with the case of diesel oil and the methanol-blended fuel in a DI diesel engine. The results are as follows : The concentrations of NOx and HC in exhaust emissions were lower than those of diesel oil as blending ratio of methanol increased, but the concentration of CO was higher slightly. As it was used the methanol-blended fuel of 10%∼20%, the exhaust emissions of NOx and HC were improved no significant difference of the engine performance in comparison with diesel oil. As the load was increased, the concentration of CO2 in exhaust emissions was high and that of O2 was low, and concentration of those in exhaust emissions was no significant difference among the fuels at constant loads.

FGR 시스템 동력 플랜트 보일러의 성능 및 배기 배출물에 미치는 재순환 배기의 영향에 관한 연구

배명환(Myung-whan Bae),정광호(Kwong-ho Jung),박성범(Sung-bum Park) 대한기계학회 2016 大韓機械學會論文集B Vol.40 No.4

자연순환식 압입 송풍식 수관보일러에 FGR시스템을 설치하여 보일러 부하 및 공기량 댐퍼개도를 파라미터로 해서 FGR률에 따른 성능 및 배기 배출물에 미치는 재순환 배기의 영향을 조사하였다. 본 연구의 목적은 NOx 배출물을 저감시키기 위하여 동력플랜트 보일러에 FGR시스템을 적용하는 것이다. 연소를 활성화시키기 위해 0 ∼ 20%의 연소용 공기를 화염 내에 공급한다. 공기상자 상부에 설치된 2단 연소시스템의 흡입댐퍼를 0° ∼ 90° 사이에서 레버를 조작하여 열면, 버너로 공급되는 연소용 공기가 변화된다. 증발률당의 연료소비율은 FGR률의 증가에 따라 증가 혹은 감소의 명확한 경향을 나타내지 않았고, 동일 공기량 댐퍼개도에서는 FGR률이 증가할수록, 또한, 보일러 부하가 감소할수록 NOx 배출물이 감소되었다. 매연 배출물은 전기 집진기에서 86.7%의 포집효율로 매연이 제거되었기 때문에, 보일러 부하, 공기량 댐퍼 개도 및 FGR률의 운전조건에 관계없이 극소량의 매연이 배출되었다. The effect of recirculated exhaust gas on performance and exhaust emissions with FGR rate are investigated by using a natural circulation, pressurized draft and water tube boiler with FGR system operating at several boiler loads and over fire air damper openings. The purpose of this study is to apply the FGR system to a power plant boiler for reducing NOx emissions. To activate the combustion, the OFA with 0 to 20% is supplied into the flame. When the suction damper of two stage combustion system installed in the upper side of wind box is opened by handling the lever between 0° and 90°, also, the combustion air supplied to burner is changed. It is found that the fuel consumption rate per evaporation rate did not show an obvious tendency to increase or decrease with rising the FGR rate, and NOx emissions at the same OFA damper opening are decreased, as FGR rates are elevated and boiler loads are dropped. While a trace amount of soot is emitted without regard to the operation conditions of boiler load, OFA damper opening and FGR rate, because soot emissions are eliminated by the electrostatic precipitator with a collecting efficiency of 86.7%.

합성가스 배기분사 기술의 개발

양승일(Seung-Il Yang),원상연(Sang-Yeon Won),송춘섭(Chun-Sub Song),박영준(Young-Joon Park),조용석(Yong-Seok Cho) 한국자동차공학회 2007 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

During a cold start period of SI engines, increasing temperature of exhaust gas is a key strategy to reduce a light-off time of a three way catalyst. This study performed injection of synthetic gas in exhaust manifold to increase exhaust gas temperature and reduce harmful emissions. Also, this study tried to evaluate changes of exhaust gas temperature and harmful emission through controls of engine operating conditions such as ignition timing and lambda control. Experimental results showed that combustion of synthetic gas in the exhaust manifold is effective in reduction of harmful emissions and decrease of the light-off time. This study also found that retarded ignition timing and increased air/fuel ratio with ESGI is effective in increasing exhaust gas temperature and reducing harmful emissions. Changing engine control variables under stable combustion condition of the engine can increase greatly effect of combustion of synthetic gas.

대형 2행정 디젤엔진의 SCR 및 EGR 시스템에 의한 NOx 배출물 저감 특성에 관한 연구

배명환(Myung-whan Bae),류지호(JiHo Ryu),김성완(SeongWan Kim),박희성(Hui-seong Park) 대한기계학회 2020 大韓機械學會論文集B Vol.44 No.7

본 연구의 목적은 선박용 대형 2행정 디젤엔진에 있어서 NOX 배출물에 대한 Tier III 규제값에 따르는 EGR 시스템의 적용 가능성을 확인하는 것이다. 디젤엔진에 Miller 사이클, SCR 및 EGR 시스템을 적용하여 엔진부하에 따른 최대 연소압력, 최대 압축압력, 배기온도, 연료소비율, O₂ 및 NOX 배출물을 실험에 의해 측정하여 비교하였다. 실험 결과는 Miller 사이클을 적용한 경우, 연비는 SCR 및 EGR 시스템보다 높았고, ISO 수정식에 의한 NOX 배출물의 최종 산정값은 Tier II 규제값을 만족하였다. 또한, SCR 및 EGR 시스템을 적용하여 측정한 NOX 배출물의 ISO 수정식에 따른 산정값은 Tier III 규제값을 만족하였고, EGR 시스템에 있어서 NOX 배출물의 산정값은 SCR 시스템보다 0.4 g/kWh 더 많았지만, EGR 시스템 적용에 의해 규제값을 만족시킬 수 있음을 알았다. The purpose of this study is to identify the applicability of EGR system complying with the Tier III regulation values for NOx emissions in a marine large two-stroke diesel engine. The Miller cycle, SCR and EGR systems were applied to the diesel engine, and the maximum combustion pressure, maximum compression pressure, exhaust temperature, fuel consumption rate, and the O₂ and NOx emissions as a function of engine load in each case were experimentally measured and subsequently compared. It was concluded that the fuel economy was higher than those of SCR and EGR systems, and the final estimated NOx emissions bases on the modified ISO formula satisfied the Tier II regulation values when the Miller cycle was applied. In addition, it was found that the estimated values of NOx emissions measured by applying the SCR and EGR systems corresponding to the modified ISO formula met in the Tier III regulation values, and this value of NOx emissions by EGR system was 0.4 g/kWh more than that of SCR system, but the regulation value could be met by the application of EGR system.

가솔린엔진 운행자동차 배기 배출물에 미치는 튜닝 흡기 및 배기 시스템의 효과에 관한 연구

배명환,구영진,박희성 대한기계학회 2019 大韓機械學會論文集B Vol.43 No.5

The purpose of this study is to obtain the basic data of engine tuning inspection by confirming the working possibility of effective engine tuning and identifying the characteristics of tuned engine that are no safety and environmental problems in a driving car of gasoline engine. The actual driving car with a four-cycle, four-cylinder DOHC, turbo-intercooler, water-cooled gasoline engine operating under four types of non-tuning, and tuning 2-1, 2-2 and 2-3 was applied to investigate the effects of tuned engine on the characteristics of excess air ratio and exhaust emissions by the low speed idle and acceleration simulation mode inspections. The tuned parts of gasoline engine in a driving car include the intake manifold, intake pipe, air filter, exhaust manifold, exhaust pipe and silencer. It was found that the measured values of CO emission, THC emissions and excess air ratio by the low speed idle inspection method, and NOX, CO and THC emissions by the acceleration simulation mode inspection method for the gasoline non-tuned and tuned engines of driving car were all satisfied with the inspection standard without any environmental problems. However, the measured values of tuned engine were greater than those of non-tuned engine. 본 연구의 목적은 가솔린엔진 운행자동차에 있어서 안전과 환경에 문제가 없는 효과적인 엔진튜닝의 작업가능성을 확인하고, 튜닝엔진의 특징을 파악하여 엔진튜닝 검사의 기초자료를 확보하는 것이다. 저속 공회전 및 정속 모드 검사에 의해 공기과잉률 및 배기 배출물을 측정해 튜닝엔진의 효과를 조사하기 위하여 4행정, 4기통 DOHC, 터보 인터쿨러, 수냉 가솔린엔진에 대한 비튜닝 및 튜닝 2-1, 2-2, 2-3의 4종류를 실제 운행자동차에 적용하였다. 운행자동차에 대한 가솔린엔진의 튜닝부분은 흡기 다기관, 흡기 파이프, 공기필터, 배기 다기관, 배기 파이프 및 소음기이다. 운행자동차 가솔린 비튜닝 및 튜닝 엔진에 대해 저속 공회전 검사방법에 의한 CO 배출물, THC 배출물 및 공기과잉률과 정속모드 검사방법에 의한 NOX, CO 및 THC 배출물 측정값은 모두 환경에 대한 문제가 없이 검사기준에 만족하였지만, 이 측정값들은 튜닝엔진의 경우가 비튜닝엔진보다 더 증가되었음을 알았다.

EGR 시스템이 직접 분사식 디젤엔진의 배기배출물에 미치는 영향에 관한 연구

장세호(S. H. Jang) 한국동력기계공학회 2004 한국동력기계공학회 학술대회 논문집 Vol.- No.-

The direct injection diesel engine is one of the most efficient thermal engines. For this reason DI diesel engines are widely used for heavy-duty applications. But the world is faced with very serious problems related to the air pollution due to the exhaust emissions of diesel engine. So/ that is air pollution related to exhaust gas resulted from explosive combustion should be improved. Exhaust Gas Recirculation(EGR) is a proven method to reduce NOx emissions. In this study, the experiments were performed at various engine loads while the EGR rates were set from 0% to 20%. The emissions trade-off and combustion of diesel engine are investigated. Hot and cooled EGR are achieved without cooling and with cooling respectively. It was found that the exhaust emissions with the EGR system resulted in a very large reduction in oxides of nitrogen at the expense of higher smoke emissions. Also, the reduction rates of NOx emissions for hot and cooled EGR are similar at load 20%.

가솔린기관의 합성가스 배기분사 기술의 최적화에 관한 실험적 연구

문창호(Chang-Ho Moon),장익규(Ik-Kyoo Jang),박영준(Young-Joon Park),이성욱(Seang-Wock Lee),조용석(Yong-Seok Cho) 한국자동차공학회 2008 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

During a cold-start period of an SI engine, fast increase in exhaust gas temperature is very crucial to improve emission due to the enhancement of catalytic performances. Synthetic gas reformed from hydrocarbon-based fuel consists of H₂, CO and N₂. Hydrogen contained in the synthetic gas is very useful species in chemical process due to its wide flammability range and fast burning speed. In this study, ESGI(Exhaust Synthetic Gas Injection) system is used to shorten the light-off time of a three-way catalyst through combustion of synthetic gas injected in exhaust manifold, during cold-start period of an SI engine. Engine control variables such as synthetic gas injection pressure, air-fuel ratio, activation time of catalyst heating function and timings of air-fuel ratio control are varied precisely using an engine management system in order to find out the tendencies of the temperature variation of the catalyst and harmful emissions. Optimized injection pressure and engine variables are suggested for the reduction in harmful exhaust emission.

인터페이스 회로를 적용한 디젤기관의 배출가스특성에 관한 실험적 연구

한영출,김대열,백두성 한국공작기계학회 2003 한국생산제조학회지 Vol.12 No.6

In order to collect the engine performance data and determine optimum engine conditions, engine performance test based on interface unit were tested. This paper was carried out that engine' performance was developed using interface unit between personal computer and diesel engine. The results of the study are summarized as follows: Interface unit was developed. By using PAL, Simulation was carried in order to logic's inspection. From this test, NOx were decreased, otherwise PM were increased. By using EGR system, PM were increased by twice in the high load ranges, it was not seen to come into effect in the low load ranges. This system was tested D13 mode, the results were decreased more than 50% in the NOx emission.

CPP 추진 선박의 운전 모드에 따른 기관성능 및 배기배출물 특성에 관한 연구

김상암,왕우경 한국동력기계공학회 2022 동력시스템공학회지 Vol.26 No.6

The engine performance and exhaust gas emissions of a ship equipped with a controllable pitch propeller and a medium-sized medium-speed diesel engine were compared according to the engine load in constant and combined mode. The cylinder pressure diagram, indicated mean effective pressure, specific fuel consumption, navigation distance to unit fuel consumption and air ratio were used to evaluate the engine performance and the emission rates of carbon dioxide, carbon monoxide, nitrogen oxides and smoke concentration were used to evaluate the exhaust gas emissions. According to the results, the engine performance and exhaust emission characteristics under a high load were similar in constant mode and combined mode. In the case of operating an engine under medium load, it was possible to reduce the fuel consumption and carbon dioxide emission rate by setting the operation mode of a controllable pitch propeller to the combined mode, but the emission rate of nitrogen oxides was slightly increased. It is thought that results of this study can provide the reference data that can reduce the carbon dioxide emission to prevent global warming and that can also improve the engine performance when selecting the operating mode of a controllable pitch propeller on the ship with a controllable pitch propeller equipment.