H2/Air 비예혼합화염의 화염신장율에 따른 NO 생성경로의 상세해석

Abstract

Detailed analysis of NO formation routes and its contributions with strain rate in hydrogen/air flames were numerically investigated. LiG detailed reaction mechanism has been used for calculation, which is compared with experimental data in literature. It shows good agreement with experiment for both temperature and NO mole fraction. Three routes have been found important for NO formation in hydrogen flames. These are the Thermal route, NNH route and N2O route. Strain rate were varied to discuss the EINO reduction trend in hydrogen nonpremixed flames, which are analyzed by each NO formation routes. As a result , as the strain rate increase, EINO decrease sharply until strain rate 100s -1 and decrease slowly until strain rate 310s -1 again, after that EINO keeps nearly constant. It can be identified that EINO trend with the strain rate is well explained by a combination of variation of production rate of above Thermal, NNH and N2O route. Also result of Thermal-Mech. that includes only thermal NO reaction is compared with those of Full-Mech. . As a result, It can be identified that there was difference between the two results of calculation. It is attributed to result that Thermal-mech did not consider contributions of NNH and N2O route. From these result, we can conclude that NOx emission characteristics of hydrogen nonpremixed flames should consider contributions of above three routes simultaneously.