Large Eddy Simulation of NO Formation in Non-Premixed Turbulent Jet Flames with Flamelet/Progress Variable Approach  

作　　者：WAN Jiawei GUO Junjun WEI Zhengyun JIANG Xudong LIU Zhaohui 

机构地区：[1]State Key Laboratory of Coal Combustion,School of Energy and Power Engineering,Huazhong University of Science and Technology(HUST),Wuhan 430074,China [2]CCRC,King Abdullah University of Science and Technology(KAUST),Thuwal 23955-6900,Kingdom of Saudi Arabia

出　　处：《Journal of Thermal Science》2024年第6期2399-2412,共14页热科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(51906075);the National Key Research and Development Program of China(2019YFE0100100).

摘　　要：To improve the NO modelling in turbulent flames,the flamelet/progress variable(FPV)model is extended by introducing NO mass fraction into the progress variable and incorporating an additional NO transport equation.Two sets of flamelet databases are tabulated with progress variables based on major species and NO mass fraction,respectively.The former is used for the acquisition of the main thermochemical variables,while the latter is employed for NO modelling.Moreover,an additional transport equation is solved to obtain the NO mass fraction,with the source term corrected using the scale similarity method.Model assessments are first conducted on laminar counterflow diffusion flames to identify lookup-related errors and assess the suitability of progress variable definitions.The results show that the progress variables based on major species and NO could correctly describe the main thermochemical quantities and NO-related variables,respectively.Subsequently,the model is applied to the large eddy simulation(LES)of Sandia flames.The results indicate that the extended FPV model improves the NO prediction,with a mean error for NO prediction at 55%,significantly lower than those of existing FPV models(130%and 385%).The LES with the extended FPV model quantitatively captures NO suppression in the mid-range of Reynolds numbers from 22400(Flame D)to 33600(Flame E),but underestimates the NO suppression at higher Reynolds numbers from 33600 to 44800(Flame F).This underprediction is primarily attributed to the underestimation of local extinction levels in flames with high Reynolds numbers.

关 键 词：Sandia flames large eddy simulation flamelet/progress variable model NO emission 

分 类 号：TQ038[化学工程]