Journal of ILASS-Korea (한국분무공학회지)

Institute for Liquid Atomization and Spray Systems-Korea (한국분무공학회)
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Effect of Atomization Characteristics of Twin Fluid Nozzle on Urea Pyrolysis

이유체 노즐 미립화 특성이 요소 열분해에 미치는 영향

  • 구건우 (경북대학교 기계공학과) ;
  • 정경열 (한국기계연구원 에너지플랜트안전연구실) ;
  • 윤현진 (구미대학교 기계공학과) ;
  • 석지권 (안동과학기술대학 미래자동차학과) ;
  • 홍정구 (경북대학교 기계공학과)
  • Received : 2015.09.09
  • Accepted : 2015.09.21
  • Published : 2015.09.30
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Abstract

Recently, there has been rising interest in applying urea-SCR systems to large marine diesel engines because the International Maritime Organization (IMO) has decided to enforce NOx reduction regulations. Generally, in the case of urea-SCR of the marine diesel engine, a type of twin fluid atomizer has been using for injection of the urea solution. This study conducted to investigate an effect of the atomization of external-mixing twin fluid nozzle on the conversion efficiency of reductant. The lab-scaled experiment device was installed to mimic the urea-SCR system of the marine diesel engine for this study. In a low temperature inflow gas condition which is similar with the exhaust temperature of large marine diesel engine, this study found that the conversion efficiency of reductant of when relative big size urea solution droplets are injected into exhaust gas stream can be larger than that of when small size urea solution droplets are injected. According to results of this study, the reason was associated with decrease of reaction rate constant caused from temperature drop of inflow gas by assist air of twin fluid atomizer.

Keywords

References

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