Tubular premixed and diffusion flames: Effect of stretch and curvature
Tubular premixed and diffusion flames: Effect of stretch and curvature
复制标题
管状预混火焰和扩散火焰：拉伸和曲率的影响
DOI：
10.1016/j.pecs.2014.01.003
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发表时间：
2014-06
影响因子：
29.5
通讯作者：
Wang, Peiyong
中科院分区：
文献类型：
--
作者：
Pitz, Robert W.;Hu, Shengteng;Wang, Peiyong
管状火焰是研究拉伸和曲率对火焰结构、消光和不稳定性影响的理想方法。管状火焰具有均匀的拉伸和曲率，每个参数可以独立变化。曲率增强或减弱对管状火焰的优先扩散作用，且加强或减弱与火焰厚度与火焰半径之比成正比。预混火焰可以在标准管式燃烧器中进行研究，在标准管式燃烧器中，单一的预混气流径向向内流动到圆柱形火焰表面，产物以相反的射流出口。在对置管状火焰中可以研究预混、扩散和部分预混火焰，其中相反的径向流动在圆柱形滞止面相遇，产物以相反的射流出口。管状火焰流动构型可以在数学上归结为沿单径向坐标的两点边值解。利用激光诱导拉曼散射对预混火焰和扩散火焰的温度和主要组分浓度进行了非侵入式测量。激光对火焰结构的测量与管状火焰的数值模拟结果吻合较好。由于管状火焰中优先扩散效应的强烈增强，理论与数据的比较对分子输运模型和化学动力学机制非常敏感。弯曲型管状火焰的加强或减弱会增加或减小管状火焰的消光应变率。对于稀薄的氢气-空气混合物，管状火焰的消光应变率可能比相应的对置射流火焰高出许多倍。在预混和非预混条件下，都可以形成更复杂的蜂窝状火焰，其周围有局部熄灭的高度弯曲的火焰单元。在氢燃料预混管状火焰中，热扩散火焰的不稳定性导致形成远离熄灭的均匀对称的花瓣火焰。在逆流管状扩散火焰中，热扩散火焰的不稳定性导致蜂窝状火焰非常接近熄灭。这两种火焰都是进一步研究火焰曲率和消光的候选对象。
Tubular flames are ideal for the study of stretch and curvature effects on flame structure, extinction, and instabilities. Tubular flames have uniform stretch and curvature and each parameter can be varied independently. Curvature strengthens or weakens preferential diffusion effects on the tubular flame and the strengthening or weakening is proportional to the ratio of the flame thickness to the flame radius. Premixed flames can be studied in the standard tubular burner where a single premixed gas stream flows radially inward to the cylindrical flame surface and products exit as opposed jets. Premixed, diffusion and partially premixed flames can be studied in the opposed tubular flame where opposed radial flows meet at a cylindrical stagnation surface and products exit as opposed jets. The tubular flame flow configurations can be mathematically reduced to a two-point boundary value solution along the single radial coordinate. Non-intrusive measurements of temperature and major species concentrations have been made with laser-induced Raman scattering in an optically accessible tubular burner for both premixed and diffusion flames. The laser measurements of the flame structure are in good agreement with numerical simulations of the tubular flame. Due to the strong enhancement of preferential diffusion effects in tubular flames, the theory-data comparison can be very sensitive to the molecular transport model and the chemical kinetic mechanism. The strengthening or weakening of the tubular flame with curvature can increase or decrease the extinction strain rate of tubular flames. For lean H2-air mixtures, the tubular flame can have an extinction strain rate many times higher than the corresponding opposed jet flame. More complex cellular tubular flames with highly curved flame cells surrounded by local extinction can be formed under both premixed and non-premixed conditions. In the hydrogen fueled premixed tubular flames, thermal-diffusive flame instabilities result in the formation of a uniform symmetric petal flames far from extinction. In opposed-flow tubular diffusion flames, thermal-diffusive flame instabilities result in cellular flames very close to extinction. Both of these flames are candidates for further study of flame curvature and extinction.
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DOI：
10.1299/jsmeb.46.190
发表时间：
2003-02
期刊：
Jsme International Journal Series B-fluids and Thermal Engineering
影响因子：
--
作者：
Kenji Yoshida;T. Takagi
通讯作者：
Kenji Yoshida;T. Takagi
影响因子：
3.6
作者：
Kulatilaka, Waruna D.;Gord, James R.;Roy, Sukesh
通讯作者：
Roy, Sukesh
影响因子：
1.9
作者：
T. M. Brown;M. Tanoff;R. Osborne;R. Pitz;M. Smooke
通讯作者：
T. M. Brown;M. Tanoff;R. Osborne;R. Pitz;M. Smooke
影响因子：
4.4
作者：
T. Takagi;Zhenliang Xu
通讯作者：
T. Takagi;Zhenliang Xu
DOI：
10.1007/3-540-19181-x_83
发表时间：
1988
期刊：
Lecture Notes in Physics
影响因子：
--
作者：
S. Ishizuka
通讯作者：
S. Ishizuka