대형 디젤 엔진의 연료 분사 노즐 형상이 NOx 발생량 및 연료소비율에 미치는 영향 연구

A Study on the Optimization of Fuel Injection Nozzle Geometry for Reducing NOx Emission in a Large Diesel Engine

  • 김기두 (현대중공업 산업기술연구소 엔진연구실) ;
  • 하지수 (현대중공업 산업기술연구소 엔진연구실) ;
  • 윤욱현 (현대중공업 산업기술연구소 엔진연구실)
  • 발행 : 2004.11.01

초록

Numerical simulations have been carried out to investigate the effect of nozzle hole geometry on the combustion characteristics of the large diesel engine. 6S90MC-C. Spray and combustion phenomena were examined numerically using FIRE code. Wane breakup and Zeldovich models were adopted to describe the atomization characteristics and NOx formation processes. Predictions on the cylinder peak pressure and NOx emission were first verified with the experimental data to confirm the reliability of numerical calculations. The comparison results showed good agreements within the range of 0.64% and 4.6% respectively. Finally, the effects of fuel spray angle and diameter on the engine performance were investigated numerically to find the optimum nozzle hole geometry considering fuel consumption, NOx emission and heat flux of the combustion chamber wall. It was concluded that the combustion gas recirculation in cylinder by changing fuel injection direction is an effective method to reduce NOx emission by about 10% with increasing fuel oil consumption, 1.4% in a large diesel engine.

키워드

참고문헌

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