单个碳粒燃烧的活化能近似逼近解
Burning of Single Carbon Particle Approached by Activation Energy Asymptotics
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摘要: 本文把活化能近似逼近方法应用于单个碳粒在静止高温气体中的燃烧问题。对非均相反应2C+O2→2CO和C+CO2→2CO及处于平衡态下的气相反应2CO+O2⇔2CO2都加以了考虑。研究发现碳粒的燃烧过程主要在扩散极限阶段完成,但在加热阶段与扩散极限阶段之间有四个短暂但相当复杂的阶段。本文还举例对活化能近似逼近解法与精确的数值解法进行了比较,比较结果令人满意。Abstract: The method of activation energy asymptotics is used to treat the combustion of a single carbon particle in quiescent gas mixture with high temperature. Both heterogeneous reactions 2C+O2 →2CO, C+CO2→2CO and homogeneous reaction 2CO+O2 2CO2 are considered. It is shown that the burning of the particle principally is carried out during a diffusion-limited period. Four brief and complex periods through which the history of the particle evolves from a heat-up period to the diffusion-limited period are described. A comparison between results of activation energy asymptotics and exact numerical solutions is given. The agreement is considered satisfactory.
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