Influences of different diluents on ignition delay of syngas at gas turbine conditions：A numerical study  

作　　者：Dong He Weiping Yan 

机构地区：[1]MOE's Key Lab of Condition Monitoring and Control for Power Plant Equipment, North China Electric Power University, Baoding 071003, China

出　　处：《Chinese Journal of Chemical Engineering》2017年第1期79-88,共10页中国化学工程学报（英文版）

基　　金：Supported by National High Technology Research and Development Program of China(2009AA05Z310)

摘　　要：Ignition delay of syngas is an important factor that affects stable operation of combustor and adding diluents to syngas can reduce NO_x emission.This paper used H_2O,CO_2 and N_2 as diluents and calculated ignition delay of syngas in temperature range of 900-1400 K and at pressures of 10 and 30 atm respectively.In high temperature range,comparing with N_2 dilution,adding H_2O and CO_2 can significantly inhibit autoignition of syngas because they have higher collision efficiencies in reaction H + O_2(+ M) = HO_2(+ M).As for low temperature conditions,adding H_2O can increase reactivity of syngas,especially under high pressure,because of its high collision efficiency in reaction H_2O_2(+ M) = 2OH(+ M).Comparing with different dilution rates shows that for syngas and operating conditions in this paper,adding N_2 mainly influences temperature rising process of syngas combustion,thus inhibiting reactivity of syngas.In addition,this paper calculated ignition delay of syngas at different equivalence ratios(φ= 0.5,1.0).Higher equivalence ratio(φ≤1) means that less air(especially N_2) needs to be heated,thus promoting ignition of syngas,Ignition delay of syngas is an important factor that affects stable operation of combustor and adding diluents to syngas can reduce NO_x emission.This paper used H_2O,CO_2 and N_2 as diluents and calculated ignition delay of syngas in temperature range of 900-1400 K and at pressures of 10 and 30 atm respectively.In high temperature range,comparing with N_2 dilution,adding H_2O and CO_2 can significantly inhibit autoignition of syngas because they have higher collision efficiencies in reaction H ＋ O_2（＋ M） = HO_2（＋ M）.As for low temperature conditions,adding H_2O can increase reactivity of syngas,especially under high pressure,because of its high collision efficiency in reaction H_2O_2（＋ M） = 2OH（＋ M）.Comparing with different dilution rates shows that for syngas and operating conditions in this paper,adding N_2 mainly influences temperature rising process of syngas combustion,thus inhibiting reactivity of syngas.In addition,this paper calculated ignition delay of syngas at different equivalence ratios（φ= 0.5,1.0）.Higher equivalence ratio（φ≤1） means that less air（especially N_2） needs to be heated,thus promoting ignition of syngas,

关 键 词：Ignition delay Reaction mechanism Combustion Kinetic modeling Syngas 

分 类 号：TK477[动力工程及工程热物理—动力机械及工程]