著者
高橋 陽一 末永 陽介 北野 三千雄 工藤 めぐみ
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 B編 (ISSN:03875016)
巻号頁・発行日
vol.71, no.712, pp.3046-3052, 2005
被引用文献数
2

Response of a cylindrical premixed flame to periodic concentration fluctuation was investigated. The flame was formed in a porous cylinder by percolating the mixture uniformly through the cylinder wall. The burner used here was devised so as to fluctuate the mixture concentration (equivalence ratio) only in the radial direction of the flow (vertically to the cylindrical flame surface) without varying the flow field. With this burner the time variations of burning velocity, burnt gas temperature and flame luminosity were measured for the lean methane-air mixture in the range of fluctuation frequency from 3 Hz to 50 Hz, and the results were examined from the viewpoint of flame curvature effects. The results show that the variation width of the burning velocity of the dynamic flame is larger than that of the static flame corresponding to the concentration fluctuation. Burnt gas temperature and flame luminosity also exhibit similar tendencies. The magnification ratio of the variation width depends on the flame curvature and the large flame curvature makes the flame sustainable even for the mixture leaner than the flammability limit of the static flame.
著者
大塚 芳郎 北野 三千雄
出版者
一般社団法人日本機械学会
雑誌
日本機械学會論文集. B編 (ISSN:03875016)
巻号頁・発行日
vol.48, no.433, pp.1818-1825, 1982-09-25

円管内層流拡散炎のすす限界を, 燃焼管直径, 燃料管直径, 空気流速および燃料流速を広範囲に変化させて, メタン, エタン, プロパン, 正ブタン, アセチレンおよびエチレンの6種の炭化水素について測定した. すす限界は, 空気比λ, 燃料流量V_fおよび燃焼管直径によって支配され, すす限界直線の傾斜d log<λ/d log V_fの大小によって, すす限界はアセチレン形とメタン系に分けられ, 前者はすすの大粒子の, 後者は小粒子の微量化する限界である.