ダブレット噴流を利用した乱流拡散火災の吹き飛び限界の向上(熱工学, 内燃機関, 動力など)

抄録

A series of experiments was performed to investigate the effect of a new combustion technique, named doublet flows, on the extension of jet diffusion flame blowoff limits. Doublet flows were formed in a concentric annulus, in which fuel jet was ejected from a nozzle set at the center of the annulus and air was sucked into an outer cylinder encompassing the nozzle. Visualization of various changes of flame morphologies triggered by doublet flows and measurement of flame lift off heights were achieved by means of normal video recording as well as image processing and treatment devices. Results showed that the blowoff limits could be extended dramatically by an increase in air-suction flow rates. The limits could be further extended by an increase in rim thickness of the nozzle. Frequent flame lift-off and reattachment occurred only in the interim of doublet flow application.