A NUMERICAL STUDY OF FLAME SPREAD AND BLOWOFF OVER A THERMALLY-THIN SOLID FUEL IN AN OPPOSED AIR-FLOW
A NUMERICAL STUDY OF FLAME SPREAD AND BLOWOFF OVER A THERMALLY-THIN SOLID FUEL IN AN OPPOSED AIR-FLOW
复制标题
热稀固体燃料在反向气流中火焰传播和吹灭的数值研究
DOI：
10.1080/00102209008951603
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发表时间：
1990
影响因子：
1.9
通讯作者：
Chiun
中科院分区：
文献类型：
--
作者：
Chiun
摘要对热薄固体燃料在反向气流中的火焰传播和吹离进行了理论研究。该模型包括准稳态，二维Navier-Slokes/动量，能量和组分方程与一步总的化学反应和二级，有限速率Arrhenius动力学气相。在与火焰前缘相连的参考系中，火焰蔓延速率v <$f）成为该问题的特征值。固相方程变得稳定，包括能量平衡与来自气相的热通量和质量平衡，包括Arrhenius热解动力学。参数研究基于可变达姆科勒数（Da），其为反向流速（u∞）的函数。随着Da的减小或u∞的增大，火焰蔓延速度v ′ f减小，火焰尺寸减小，火焰强度减弱。当Da降低到临界值时，达到放泄极限。固体燃料中的热传导有助于更高的VF，并且是接近临界温度的主要过程。
Abstract Flame spread and blowoff in an opposed air stream over a thermally-thin solid fuel is studied theoretically. The model includes the quasi-steady, two dimensional Navier-Slokes/ momentum, energy and species equations with one-step overall chemical reaction and second-order, finite-rate Arrhenius kinetics in gas phase. In a reference frame attached to the flame front, the flame spread rate v¯ f) becomes an eigenvalue for this problem. The solid phase equations become steady, consisting of an energy balance coupled with the heat flux from the gas phase and a mass balance including Arrhenius pyrolysis kinetics. The parametric study is based on a variable Damkohler number (Da) which is a function of opposed flow velocity (u∞ ). The spread rate v¯ fand the flame size are reduced and the flame becomes weaker as Da is decreased or u∞ is increased. A blowoff limit is reached when Da is lowered to a critical value. Heat conduction in the solid fuel contributes to higher VF and is the dominant process near ...