軸対称流れ場に形成される管状火炎に及ぼす回転強さの影響

Effects of Rotation on Tubular Flames in an Axisymmetric Flow Field

山本 和弘

石塚 悟

平野 敏右

日本機械学會論文集. B編

Using an axisymmetric swirl-type burner with eight inlet slits, the effects of rotation on the structure and characteristics of tubular flames have been investigated for lean methane/air mixtures.Results show that with increasing intensity of rotation, (1) the flame diameter increases and the thickness of the luminous zone decreases, (2) the fuel concentration at extinction decreases, i. e., the stable region expands, (3) the radial temperature distribution becomes an M-shaped profile, and the maximum temperature T_f increases while the local minimum temperature T_c at the center decreases,and (4) the values of T_f and T_c vary in a complicated manner in the axial direction. These results are almost consistent with those of our previous experiment, and hence, it is confirmed that the flame structure and the flame characteristics are affected by rotation. As for these phenomena, several mechanisms such as pressure diffusion, radiative heat loss, viscous energy dissipation, and energy recirculation including diffusion of radical species have been proposed. The present experimental results provide the first, basic information on this practically important phenomenon, i. e., the extension of flammable range by rotation.

Premixed Combustion

Swirling Flow

Stability

Flammability Limit

Tubular Flame

Pressure Diffusion

Structure

技術・工学 [ 500 ]

日本語

一般社団法人日本機械学会

社団法人日本機械学会

本文データは学協会の許諾に基づきCiNiiから複製したものである

[ISSN] 0387-5016

[NCID] AN00187441

[NAID] 110002403155 ～の異版である