水泥回转窑余热回收利用系统实验分析与数值模拟

发布时间：2018-03-25 23:36

本文选题：集热器　切入点：余热利用　出处：《山东大学》2015年硕士论文

【摘要】：社会经济的发展离不开能源的消耗。随着我国经济的高速发展,能源消费量也飞速增加。我国是世界上第二大能源消耗国,建材行业是排在冶金行业、化工行业后的第三能耗大户。水泥行业能耗与污染情况不容乐观,必须加强节能减排。同时,水泥回转窑表面散热量可达到3-5MW,人们往往忽略这部分热量,将其完全排入大气。因此,水泥回转窑筒体余热回收利用技术的研究,对于充分合理的利用这种资源,提高水泥厂余热梯级利用和能源利用率、有效降低余热排放的热污染、保护生态环境具有重要积极意义。本文主要工作如下所示：1.对国内外现有的水泥回转窑余热回收利用系统的结构型式,运行特点及分析方法进行了综合概述；并充分考虑回转窑实际运行情况及回转窑温度分布后,本课题组设计了一种回转窑余热回收利用系统。2.建立了集热器物理模型；对其进行网格划分,网格质量验证,网格无关性验证；设置好各个域的边界条件；选择湍流模型及辐射模型；根据实际情况,选择本文适合的求解器。3.对集热器进行数值模拟。得出不同流动型式及不同结构型式集热器,空气域和水域的温度云图。改变不同结构型式集热器水域的进口流量,得出不同流量下换热管横截面内温度分布,与实际情况相符合。改变不同结构型式集热器水域的进口流量,得出性能较好的集热器型式。改变不同结构型式集热器水域的进口流量,得出换热管外壁换热量,换热管外壁吸收辐射热量及换热管内水吸收热量的关系。4.在水泥厂设备正常运行基础上搭建了实验平台,真实反映集热器性能及对生产的影响。对集热器一些参数进行观测,记录,分析,得出不同集热器内的换热量；集热器吸热量的影响因素；并将实验结果与数值分析结果进行对比。5.对集热器进行传热过程分析,采用热网络模型,进行合理假设后,建立并求解了其传热数学模型,得出各个过程换热量和能量收支平衡情况,并与实验结果进行对比。
[Abstract]:With the rapid development of China's economy, energy consumption is also increasing rapidly. China is the second largest energy consumer in the world, and the building materials industry is ranked in the metallurgical industry. The third largest energy consumption after the chemical industry. Cement industry energy consumption and pollution situation is not optimistic, we must strengthen energy saving and emission reduction. At the same time, cement rotary kiln surface heat loss can reach 3 to 5 MWs, people often ignore this part of heat, Therefore, the research of waste heat recovery and utilization technology of cement rotary kiln cylinder can make full and reasonable use of this resource, improve the cascade utilization and energy utilization of waste heat in cement plant, and effectively reduce the heat pollution caused by waste heat emission. It is of great significance to protect the ecological environment. The main work of this paper is as follows: 1. The structure, operation characteristics and analysis methods of the existing waste heat recovery and utilization system of cement rotary kiln at home and abroad are summarized. After fully considering the actual operation of rotary kiln and the temperature distribution of rotary kiln, our team designed a rotary kiln waste heat recovery and utilization system .2.The physical model of collector was established, and the grid was divided, and the quality of grid was verified. Grid independence verification; setting up boundary conditions in each domain; selecting turbulence model and radiation model; according to the actual situation, Choose the suitable solver in this paper. 3. Carry on the numerical simulation to the collector. Get the temperature cloud diagram of different flow type and different structure type collector, air domain and water area. Change the inlet flow rate of the water area of different structure type collector, The temperature distribution in the cross section of the heat exchanger pipe at different flow rates is obtained, which is in accordance with the actual situation. Change the inlet flow rate of the water area of the collector with different structure, and get the heat transfer of the outer wall of the heat transfer pipe. The relationship between the absorption of radiation heat on the outer wall of the heat exchanger pipe and the heat absorption of water in the heat exchanger pipe. Based on the normal operation of the equipment in the cement plant, an experimental platform is built to reflect the performance of the collector and the effect on the production. Some parameters of the collector are observed. Record, analyze, get the heat transfer in different collector; influence factors of heat absorption in collector; compare the experimental results with numerical analysis results. 5. Analyze the heat transfer process of the collector, adopt the heat network model, After reasonable assumption, the mathematical model of heat transfer is established and solved, and the balance of heat transfer and energy budget of each process is obtained, and the results are compared with the experimental results.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ172.625.9;TK115

【参考文献】