| 单颗粒煤焦在大空间中燃烧的数值模拟方法及实验验证 |
| 刘雨廷, 何榕 |
| 清华大学 热能工程系, 热科学与动力工程教育部重点实验室, 北京 100084 |
| Numerical simulation method and experimental validation of a single char particle combustion model in bulk space |
| LIU Yuting, HE Rong |
| Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084, China |
摘要:
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| 摘要为了对煤焦颗粒的燃烧过程进行更精确的预测, 该文从多组分混合反应系统守恒方程出发, 构建了一套能够精确模拟煤焦颗粒燃烧过程的数值方法。该方法细致描述了煤焦颗粒边界层内发生的一系列物理化学过程, 有助于煤焦燃烧机理的研究, 计算量也不大。该方法还可以用于对流动形态较为简单的实际工况的模拟, 如煤焦颗粒在沉降炉内燃烧等。通过实验测得4种煤焦在沉降炉中燃烧的最终转化率, 并运用该方法对其进行预测, 证明了该方法的可靠性。模拟结果表明: 随着环境温度的升高, 煤焦燃烧速率加快, 颗粒边界层中O2摩尔分数下降更多, 而产物CO和CO2的摩尔分数却明显上升。 | |||
| 关键词 ：煤焦燃烧,模拟,守恒方程,沉降炉,实验验证 | |||
| Abstract：A numerical method is developed based on the conservation equations for multicomponent reacting systems to better predict char particle combustion. The advantage of this method is that many physical and chemical processes occurring in the char particle boundary layer are described in detail with less CPU time, which improves the studies of the char combustion mechanism. This method can also be used to simulate real situations with relatively simple flow patterns, like the char particle combustion in a drop tube furnace (DTF). Four chars are combusted in a DTF with their final conversions measured. The predicted char conversions compare well with the measured data to validate this method. As the ambient temperature increases, the char combustion rate becomes faster and the O2 concentration decreases while the CO and CO2 amounts strongly increase in the char particle boundary layer. | |||
| Key words：char combustionsimulationconservation equationdrop tube furnaceexperimental validation | |||
| 收稿日期: 2015-06-08 出版日期: 2016-07-01 | |||
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| 通讯作者:何榕, 教授, E-mail: rhe@mail.tsinghua.edu.cnE-mail: rhe@mail.tsinghua.edu.cn | |||
| 引用本文: |
| 刘雨廷, 何榕. 单颗粒煤焦在大空间中燃烧的数值模拟方法及实验验证[J]. 清华大学学报（自然科学版）, 2016, 56(6): 598-604. LIU Yuting, HE Rong. Numerical simulation method and experimental validation of a single char particle combustion model in bulk space. Journal of Tsinghua University(Science and Technology), 2016, 56(6): 598-604. |
| 链接本文: |
| http://jst.tsinghuajournals.com/CN/10.16511/j.cnki.qhdxxb.2016.22.018或 http://jst.tsinghuajournals.com/CN/Y2016/V56/I6/598 |
图表:
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| 图１ 沉降炉结构示意图 |
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| 表１ 原煤的工业分析结果(空干基) |
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| 表２ 原煤的元素分析结果(干燥基) |
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| 表３ 煤焦样品的平均粒径与孔隙参数 |
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| 表４ 煤焦最终转化率预测结果与实验数据的比较 |
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| 表５ 单膜模型与双膜模型的模拟结果与相对误差 |
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| 图２ 煤焦燃烧过程中煤焦颗粒温度的变化 |
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| 图３ 煤焦颗粒的转化率曲线 |
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| 图４ 煤焦颗粒的燃烧速率曲线 |
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| 图５ 煤焦燃烧过程中颗粒表面O２ 摩尔分数的变化 |
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| 图６ 煤焦燃烧过程中颗粒表面CO２ 摩尔分数的变化 |
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| 图７ 煤焦燃烧过程中颗粒表面CO 摩尔分数的变化 |
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