火灾科学
火災科學
화재과학
FIRE SAFETY SCIENCE
2012年
3期
137-146
,共10页
重要性分析%混合燃烧%框架机理%化学存活时间%敏感性系数
重要性分析%混閤燃燒%框架機理%化學存活時間%敏感性繫數
중요성분석%혼합연소%광가궤리%화학존활시간%민감성계수
Level of importance analysis%Skeletal mechanism%Mixed combustion%Chemical lifetime%Sensitivity coefficient
建立了基于重要性分析的详细化学机理分析平台,利用耦合组分化学存活时间和敏感性系数的重要性参数,确定详细机理中的准稳态组分,通过移除这些组分及其相关反应,得到了计算精度较高的框架机理。针对目前燃烧学界较为关注的混合燃烧问题,以甲烷、乙烯这两种典型低碳碳氢燃料为研究对象,对其详细化学反应机理进行了分析,利用重要性分析法构筑框架机理,并对甲烷/空气和甲烷/乙烯/空气预混火焰进行了数值计算。与详细机理相比,框架机理所涉及的组分数与基元反应数都得到了大幅度的降低,计算时间明显减少,但对火焰温度及反应物、生成物、中间组分浓度的预测与采用详细机理得到的结果吻合良好,证明了重要性分析法的有效性与可靠性。
建立瞭基于重要性分析的詳細化學機理分析平檯,利用耦閤組分化學存活時間和敏感性繫數的重要性參數,確定詳細機理中的準穩態組分,通過移除這些組分及其相關反應,得到瞭計算精度較高的框架機理。針對目前燃燒學界較為關註的混閤燃燒問題,以甲烷、乙烯這兩種典型低碳碳氫燃料為研究對象,對其詳細化學反應機理進行瞭分析,利用重要性分析法構築框架機理,併對甲烷/空氣和甲烷/乙烯/空氣預混火燄進行瞭數值計算。與詳細機理相比,框架機理所涉及的組分數與基元反應數都得到瞭大幅度的降低,計算時間明顯減少,但對火燄溫度及反應物、生成物、中間組分濃度的預測與採用詳細機理得到的結果吻閤良好,證明瞭重要性分析法的有效性與可靠性。
건립료기우중요성분석적상세화학궤리분석평태,이용우합조분화학존활시간화민감성계수적중요성삼수,학정상세궤리중적준은태조분,통과이제저사조분급기상관반응,득도료계산정도교고적광가궤리。침대목전연소학계교위관주적혼합연소문제,이갑완、을희저량충전형저탄탄경연료위연구대상,대기상세화학반응궤리진행료분석,이용중요성분석법구축광가궤리,병대갑완/공기화갑완/을희/공기예혼화염진행료수치계산。여상세궤리상비,광가궤리소섭급적조분수여기원반응수도득도료대폭도적강저,계산시간명현감소,단대화염온도급반응물、생성물、중간조분농도적예측여채용상세궤리득도적결과문합량호,증명료중요성분석법적유효성여가고성。
An analysis system for detailed chemical mechanisms based on level of importance analysis was established. Quasi- steady-state species were determined by using level of importance index, which was composed of species chemical lifetime and sensitivity coefficient. Then these species and reactions concerned were removed to get skeletal mechanism with high calculation precision. Since mixed combustion is one of the hot spots in combustion community nowadays, the typical low-carbon hydrocar- bon fuels-methane and ethylene were taken as research subject and their detailed chemical reaction mechanism was analyzed. Level of importance analysis was employed to obtain skeletal mechanisms, which were then adopted for numerical simulation of premixed methane/air and methane/ethylene/air flames. Compared with the detailed mechanism, the numbers of species and el ementary reactions in skeletal mechanisms were reduced substantially and the computation time decreased. On the other hand, the predictions of the flame temperature and species concentrations with skeletal mechanisms agreed well with those by using detailed mechanisn~ And the method of level of importance analysis is proved to be effective and reliable.