한국연소학회:학술대회논문집

The Korean Society of Combustion (한국연소학회)
권호 표지

Direct Numerical Simulation and Second-Order Conditional Moment Closure Modelling of a Turbulent Hydrocarbon Flame

난류 탄화수소화염의 직접수치해석 및 이차 조건모멘트닫힘 모델링

  • Kim, Seung-Hyun ;
  • Huh, Kang Y. ;
  • Bilger, Robert W. (School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney)
  • 김승현 (포항공과대학교 기계공학과) ;
  • 허강열 (포항공과대학교 기계공학과) ;
  • Published : 2001.11.16
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Abstract

A second-order conditional moment closure(CMC) model is applied to the prediction of local extinction in a turbulent hydrocarbon diffusion flame and compared with direct numerical simulation(DNS) results for the flame. Combustion of a hydrocarbon fuel is described by a simple two-step mechanism. A second-order correction for conditional mean reaction rate terms is made by the assumed pdf method. The results show that the second-order closure is necessary for accurate prediction of intermediate species, while first-order CMC gives good predictions for fuel, oxidant, product and temperature. Conditional variances and covariances are well predicted during an extinction process while they are overpredicted during a reignition process.

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