摘要:我国的煤炭资源丰富,且在未来相当长的一段时期内我国电力产业仍将依赖燃煤发电。然而在燃煤产业推动我国经济发展的同时也带来了诸多问题,其中氮氧化物排放造成的污染尤为明显。因此,发展先进的煤粉燃烧技术以降低NOx排放是当务之急。本文所研究的百叶窗煤粉浓缩器是水平浓淡燃烧技术的核心部件。为了探究叶片级数对其性能的影响,本文采用FLUENT软件对浓缩器内部 流体及颗粒运动进行数值模拟。通过分析发现,叶片级数对煤粉浓缩器中流场的压力分布、速度分布以及颗粒运动都有着一定的影响。当叶片数增加时,浓缩器对颗粒的浓缩效果越显著,但是总阻力损失也会随之增加。研究还发现,不同粒径的颗粒其运动轨 迹有明显差别,粒径越小,其运动状 态越接近气相;叶片级数能影响同一粒径下颗粒的运动状况。41848
毕业论文关键词: 煤粉浓缩器;数值模拟;气固两相流
Study on Numerical Simulation of Blade stage’s effect on Pulverized Coal Concentrator’s Performance
Abstract: China is rich in coal resources and the power industry will continue to rely on coal-fired generation during a long period of time. Although the coal-fired industry promotes China's economic, it also brings a lot of problems, especially the impact of nitrogen oxides. Therefore, the development of advanced coal combustion technology becomes the first priority. This paper studied the Louver Coal Concentrator, which is the core component of Horizontal Bias Combustion Technology. In order to make a thorough inquiry of the impact about the effect of blade stages on the Louver Coal Concentrator , this paper use the FLUENT software launched studies on the gas-solid two phase flow. The analysis revealed that blade stages has a certain influence on pressure distribution, velocity distribution and particle motion in the pulverized coal concentrator . When increasing the number of blades, the concentrating effect is more significant, but the total resistance loss also increases. The study also found that different particles are different in movement, the larger the particle is, the more obvious the difference is.
Keywords: Pulverized Coal Concentrator;Numerical Simulation;Two-phase flow
目录
1绪论 1
1.1课题背景及意义 1
1.2百叶窗煤粉浓缩器概述 2
1.2.1 百叶窗煤粉浓缩器的结构和原理 2
1.2.2 百叶窗煤粉浓缩器的性能指标 2
1.3 本课题的研究动态 3
1.4本课题的研究内容及方法 4
1.4.1 研究内容 4
1.4.2 研究方法 4
2 FLUENT软件及相关模型介绍 6
2.1 FLUENT概述 6
2.2 FLUENT的组成及应用 6
2.2.1 FLUENT的组成 6
2.2.2 FLUENT的应用 7
2.3 FLUENT的特点 8
2.3.1 网格技术 8
2.3.2 数值技术 8
2.4 百叶窗煤粉浓缩器内气固两相流模型 9
2.4.1 离散相模型 9
2.4.2 颗粒与湍流作用 10
2.4.3 气相和颗粒相相互作用