http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
임석연,최두석,류정인 한국자동차공학회 2009 International journal of automotive technology Vol.10 No.2
The purpose of this study is to understand the operational characteristics of a diesel engine that uses BD20 reformed by ultrasonic energy irradiation. In particular we study the effects of tuning injection delay and EGR rate. BD containing about 10% oxygen has attracted attention due to soaring crude oil prices and environmental pollution. This oxygen decreases soot by promoting combustion, but it also increases NOx. To solve this problem, injection timing may be delayed or an EGR system may be applied. These adjustments normally lower engine power and increase exhaust emission but, in using fuel reformed by ultrasonic energy irradiation (which is changed physically and chemically to promote combustion), we may hope to circumvent this problem. To control the duration of the ultrasonic energy irradiation, the capacity of the chamber in an ultrasonic energy fuel supply system was tested at 550cc and 1100cc capacities. As for the results of the experiment, we could identify the optimum EGR rate by investigating the engine performance and the characteristics of exhaust emissions according to the injection timing and the EGR rate while ultrasonically irradiated BD20 was fed to a commercial diesel engine. With UBD20 (at an injection timing of BTDC 16˚), the optimum EGR rate, giving satisfactory engine performance and exhaust emissions characteristics, was in the range of 15~20%. The purpose of this study is to understand the operational characteristics of a diesel engine that uses BD20 reformed by ultrasonic energy irradiation. In particular we study the effects of tuning injection delay and EGR rate. BD containing about 10% oxygen has attracted attention due to soaring crude oil prices and environmental pollution. This oxygen decreases soot by promoting combustion, but it also increases NOx. To solve this problem, injection timing may be delayed or an EGR system may be applied. These adjustments normally lower engine power and increase exhaust emission but, in using fuel reformed by ultrasonic energy irradiation (which is changed physically and chemically to promote combustion), we may hope to circumvent this problem. To control the duration of the ultrasonic energy irradiation, the capacity of the chamber in an ultrasonic energy fuel supply system was tested at 550cc and 1100cc capacities. As for the results of the experiment, we could identify the optimum EGR rate by investigating the engine performance and the characteristics of exhaust emissions according to the injection timing and the EGR rate while ultrasonically irradiated BD20 was fed to a commercial diesel engine. With UBD20 (at an injection timing of BTDC 16˚), the optimum EGR rate, giving satisfactory engine performance and exhaust emissions characteristics, was in the range of 15~20%.
바이오디젤 혼합연료를 적용한 4 실린더 커먼레일 디젤엔진에서 EGR율이 연소 및 배기특성에 미치는 영향
정규수(Kyusoo Jeong),이동곤(Donggon Lee),연인모(Inmo Youn),노현구(Hyungu Roh),이창식(Changsik Lee) 한국자동차공학회 2010 한국자동차공학회 학술대회 및 전시회 Vol.2010 No.11
This study describes the effect of EGR rate on the combustion and emissions characteristics of a four cylinder CRDI diesel engine using biodiesel(Soybean oil) blended diesel fuel. The experimental fuel is composed of 30% biodiesel(Soybean) and 70% ULSD(Ultra low sulfur diesel) by volumetric ratio. The experiment of engine emissions and performance characteristics were performed under the various EGR rate. The experimental results show that ignition delay was extended with increasing EGR rate, and maximum combustion pressure and heat release gradually were decreased. Comparing biodiesel blended fuel and ULSD, the injection quantity of biodiesel blended fuel was more increased than ULSD. The emission results show that NOx emission of biodiesel blended fuel with increasing EGR rate shows more higher than that of ULSD. However, in the case of biodiesel blended fuel, HC, CO and soot emissions were decreased than that result of ULSD.
임석연,Y. S. SONG,J. I. RYU 한국자동차공학회 2008 International journal of automotive technology Vol.9 No.3
The purpose of this study is to understand the physical and chemical characteristics of biodiesel blended fuel reformed by ultrasonic energy irradiation. To do this, a mixture of commercial diesel fuel and biodiesel was compared and analyzed according to whether or not ultrasonic energy irradiation was performed and the duration of irradiation. The results of the experiments indicate that when ultrasonic energy irradiation was performed on biodiesel blended fuel, its viscosity decreased by 3−7%. In the case of BD20, when ultrasonic energy irradiation was performed, its Sauter mean diameter (SMD) dropped by 12% on average. As the irradiation duration increased, the volume ratio of olefins increased up to a maximum of 2.7%, and the higher heating value increased to a maximum of 5.8%. On the contrary, the ratio of aromatics decreased by a maximum of 2.7%, and BI decreased by a maximum of 7%.