Flame Propagation in CH4/H2/O2 Blended Mixtures in Smooth Tubes of Millimeter-Scale. Issue 8 (2nd August 2016)

• Record Type: Journal Article
• Authors: Hsu, Yao-Chung; Chao, Yei-Chin; Chung, Kung-Ming
• Is Part Of: Combustion science and technology. Volume 188:Issue 8(2016)
• Page Start: 1239
• Page End: 1248
• Publication Date: 2016-08-02
• Subjects: Blended fuel -- Detonation -- Flame -- Millimeter-scale tubes; Combustion -- Periodicals; Combustion engineering -- Periodicals; 541.36105
• DOI: 10.1080/00102202.2016.1177033
• Languages: English
• ISSNs: 0010-2202

Abstract

ABSTRACT: There are few studies of flame propagation and the initiation of detonation for blended mixtures. In this article, an experimental study is conducted to investigate the acceleration of a flame in stoichiometric methane/hydrogen/oxygen (CH4 /H2 /O2 ) mixtures in millimeter-scale smooth tubes. In the 1.0- and 1.5-mm tubes, there is no flame acceleration or detonation initiation. The flame propagates at a speed of several m/s. This may occur because of the heat loss on a non-adiabatic wall and the condensation of water vapor. When the molar fraction of CH4 in a 3.0-mm tube is larger than 0.3, detonation is initiated. The early stage of flame propagation is divided into propagation at a constant velocity, deceleration, and exponential acceleration. An increase in the molar fraction of CH4 induces a pulsating propagation of a flame.