Saitama University Department of Mechanical Engineering, Faculty of Engineering
Saitama University Department of Mechanical Engineering, Faculty of Engineering
Saitama University Department of Mechanical Engineering, Faculty of Engineering
出版者
航空宇宙技術研究所
出版者（英）
National Aerospace Laboratory (NAL)
雑誌名
航空宇宙技術研究所特別資料
雑誌名(英)
Special Publication of National Aerospace Laboratory
A numerical study is performed of the effects on the stabilization of a diffusion flame in a flat plate boundary layer, into which fuel gas is injected vertically from the surface of the wall with a uniform velocity. A theoretical model is presented to couple fluid dynamics, chemistry and heat transfer on the surface of the flat plate. Governing equations of two-dimensional, compressible Navier-Stokes momentum, energy and chemical species are used and are numerically integrated by means of a finite difference method. Chemical reaction model is one-step, overall irreversible one with second-order, finite rate Arrhenius kinetics. Lots of computations are performed and five cases are discussed on understanding effects of Nusselt number, Damkohler numbers and free stream Reynolds number. By varying the Nusselt number, multiregion structures of mixing only, premixing- and diffusion-controlled reactions are observed near the leading edge of the flame. In the region of the premixing-controlled reaction, fuel lean and rich reactions can be found. As the flow velocity decreases, the flame tends to have a large stand-off distance and more fuel mass is transferred upstream of the burner to enforce the local reaction and to improve the stabilization of the flame.
Numerical study on stabilization of a diffusion flame over a flat plate
nalsp0027005.pdf
(543.04KB)
