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Urea 수용액 분사용 인젝터의 분무 특성과 배기관내 분무 거동 특성

The Spray Characteristics and Spray Behavior Characteristic in Exhaust Gas Flow of Urea Solution Injector

  • Oh, Jung-Mo (Dept. of Mechanical Engineering, Hanyang Univ.) ;
  • Han, Young-Deok (Dept. of Mechanical Engineering, Hanyang Univ.) ;
  • Kim, Ki-Bum (Dept. of Mechanical Engineering, Hanyang Univ.) ;
  • Lee, Ki-Hyung (Dept. of Mechanical Engineering, Hanyang Univ.)
  • 투고 : 2010.06.30
  • 심사 : 2010.09.10
  • 발행 : 2010.11.01

초록

디젤 엔진은 가솔린 엔진에 비해 열효율이 높고 이산화탄소 배출량이 적다. 그러나 입자상물질(PM)과 질소산화물(NOx)의 배출량이 가솔린 엔진보다 많은 단점을 가지고 있다. 디젤 엔진의 연소 배출물 중 질소 산화물을 저감시키기 위하여 LNT와 Urea-SCR과 같은 후처리 시스템이 최근 활발히 연구되고 있다. Urea-SCR은 Urea 수용액을 공급하기 위한 2차 분사 시스템이 필요하고, 분사된 Urea 수용액의 분무 거동 특성과 균일도에 따라서 촉매의 효율이 크게 달라진다. 본 연구에서는 배기관에 분사된 Urea 수용액의 분무균일도를 향상시키기 위하여 인젝터의 기초 분무 특성을 파악하였고, 모사배기관 시스템과 가시화 장비를 이용하여 배기관내에서의 분무 거동 특성을 파악하였다.

Recently, many technologies have been developed in order to satisfy stringent emission regulations. However, in the case of diesel engines, the stringent emission regulations with respect to NOx and PM have not yet been satisfied. A dramatic reduction in the NOx and PM emissions could be achieved by using after-treatment systems such as lean NOx trap (LNT) and urea-SCR systems. However, the high temperature in the exhaust pipe affects the spray behavior of the secondary injector, which is used for supplying the Urea-SCR. Because of this high temperature, it is difficult to achieve uniform distribution of the reducing agent in the manifold. In this paper, the characteristics of a urea-SCR injector used for injecting in the exhaust pipe are presented. The purpose of this study was to investigate the spray characteristics of the injector, such as the spray angle, injection quantity, and SMD. In addition, laser diagnostics and high-speed-camera images were used to analyze the injector spray characteristics and to present a distribution of reduction in the transparent manifold.

키워드

참고문헌

  1. Heywood, J. B., 1988, "Internal Combustion Engine Fundamentals," McGraw Hill.
  2. Eastwood, P., 2000, "Critical Topics in Exhaust Gas After-Treatment," Research studies press Ltd.,.
  3. Oh, J. T., Seo, J. W., Lee, K. I., Park, J. I., Choi, Y. H. and Lee, J. H., 2007, “Visualization of Urea Mixing Characteristics by Mixer and Diffuser in SCR system,” KSAE 2007.
  4. Choi, J. H., Choi, Y. S., Cho, I. E. and Lee, S. W., 2007, "A Study on the Distribution of Injected Urea into Exhaust Pipe in the SCR System," KSAE 2007.
  5. Oh, J. M., Lee, K. H. and Lee, J. H., 2008, “A Study on the Optimal Injection Conditions for an HC-LNT Catalyst System with a 12-Hole Type Injector," Journal of Thermal Science and Technology, Vol. 3, No. 2, pp. 278-291. https://doi.org/10.1299/jtst.3.278
  6. Jeong, H. Y., Lee, K. H. and Ikeda, Y., 2007, "Investigation of the Spray Characteristics for a Secondary Fuel Injection Nozzle Using a Digital Image Processing Method," Meas. Sci. Technol., Vol. 18, pp. 1591-1602. https://doi.org/10.1088/0957-0233/18/5/051
  7. Oh, J. M., Lee, K. H. and Jeong, H. Y., 2008, "Study on the Spray Behavior and Diesel Fuel Distribution Characteristics of a Secondary Injector for a Lean NOx Trap Catalyst," Energy & Fuels, Vol. 22, pp. 1527-1534. https://doi.org/10.1021/ef800045t