title: Experimental study on a comparison of typical premixed combustible gas-air flame propagation in a horizontal rectangular closed duct.
abstract: Research surrounding premixed flame propagation in ducts has a history of more than one hundred years. Most previous studies focus on the tulip flame formation and flame acceleration in pure gas fuel-air flame. However, the premixed natural gas-air flame may show different behaviors and pressure dynamics due to its unique composition. Natural gas, methane and acetylene are chosen here to conduct a comparison study on different flame behaviors and pressure dynamics, and to explore the influence of different compositions on premixed flame dynamics. The characteristics of flame front and pressure dynamics are recorded using high-speed schlieren photography and a pressure transducer, respectively. The results indicate that the compositions of the gas mixture greatly influence flame behaviors and pressure. Acetylene has the fastest flame tip speed and the highest pressure, while natural gas has a faster flame tip speed and higher pressure than methane. The Bychkov theory for predicting the flame skirt motion is verified, and the results indicate that the experimental data coincide well with theory in the case of equivalence ratios close to 1.00. Moreover, the Bychkov theory is able to predict flame skirt motion for acetylene, even outside of the best suitable expansion ratio range of 6<E<8.
authors.affiliation: University of Science and Technology of China, Hefei 230026, People's Republic of China; City University of Hong Kong, Hong Kong, People's Republic of China.
authors.forename: Kaiqiang
authors.initials: K
authors.lastname: Jin
authors.affiliation: University of Science and Technology of China, Hefei 230026, People's Republic of China.
authors.forename: Qiangling
authors.initials: Q
authors.lastname: Duan
authors.affiliation: City University of Hong Kong, Hong Kong, People's Republic of China.
authors.forename: K M
authors.initials: KM
authors.lastname: Liew
authors.affiliation: University of Science and Technology of China, Hefei 230026, People's Republic of China.
authors.forename: Zhongjing
authors.initials: Z
authors.lastname: Peng
authors.affiliation: University of Science and Technology of China, Hefei 230026, People's Republic of China.
authors.forename: Liang
authors.initials: L
authors.lastname: Gong
authors.affiliation: University of Science and Technology of China, Hefei 230026, People's Republic of China. Electronic address: sunjh@ustc.edu.cn.
authors.forename: Jinhua
authors.initials: J
authors.lastname: Sun
keywords: Comparison; Flame skirt motion; Flame tip speed; Premixed flame; Pressure dynamics