摘要
研究了热量再循环和不同式Lewis数,对有机尘埃微粒燃烧的作用.在微型燃烧室中,由于热量再循环的影响更加显而易见,所以建立更好的模拟微型燃烧室性能的计算模型显得十分必要.为了模拟有机尘埃微粒的燃烧,假定尘埃微粒首先被气化,氧化成为一种化学结构已知的气相,接着假定该可燃气体的化学结构为甲烷.为了研究火焰的结构和求解控制方程,认为火焰结构由3个区域组成,即预热气化区、反应区和后火焰区.通过从后火焰区到预热区的排热来评价再循环现象.问题如下分步求解:首先对各区域的控制方程无量纲化;接着对各区域应用必要的边界条件和协调条件;然后按分析模型,对控制方程以及必要的边界条件和协调条件,同时进行求解.表明,再循环和不同式Lewis数,对有机尘埃微粒的燃烧特性有着显著的影响,得到不同微粒半径时的燃烧速度曲线和温度曲线等.结果与已发表的试验数据吻合.
The role of recirculation and non-tmity Lewis number on the combustion of organic dust particles were investigated. Since recirculation effect is more noticeable in micro-combustots, it is necessary to propose a modeling approach of this phenomenon to better simulate the performance of micro-combustors. In this research, in order to model the combustion of organic dust particles, it was assumed that the dust particles vaporize first to yield a known chemical structure which was oxidized in the gas phase, and the chemical structure of this gaseous fuel was assumed methane. To study the flame structure and solve the governing equations, it was considered that the flame structure consists of three zones titled the preheat-vaporization zone, the narrow reaction zone and finally the post flame zone. The recirculation phenomenon was evaluated by entering the exhausted heat from the post flame zone into the preheat zone. The solution was based on the following approach. First, the governing equations in each zone were nondimensionalized. Then the needed boundary and matching conditions were applied in each zone. After that, these equations and the required boundary and matching conditions were sim- ultaneously solved with the analytical model. Consequently, the remarkable effects of recirculation and nonunity Lewis number on the combustion characteristics of the organic dust particles such as burning velocity and temperature profiles for different particle radii are obtained. The results show reasonable agreement with published experimental data.
出处
《应用数学和力学》
CSCD
北大核心
2010年第6期659-669,共11页
Applied Mathematics and Mechanics
作者简介
作者简介：AboozarFanaee（联系人．E-mail：sab．famech@yahoo．com）．
