式槽太阳能热发电系统中内置扰流柱群集热管的换热特性研究本科论文.doc

摘要 8%，集热器温度场分布更加均匀。 关键词：太阳能热流；强化热；；应力Abstract There are three main advantages of the photo-thermal utilization of solar energy：（1）pollution-free（2）zero-emission（3）nonuse of fossil fuel. The four main kinds of solar energy photo-thermal utilization are parabolic trough collectors, parabolic dish collectors, heliostats and linear Fresnel reflectors. At present, among these, the parabolic trough collectors is the most commercially utilized.?A series problems of the parabolic trough collector are: low efficiency of heat transfer, non-uniform temperature distribution and high heat transfer temperature difference. An innovative inserted pin-fin arrays tube is introduced to realize heat transfer augmentation, homogenizing temperature distribution and promoting efficiency. Primarily, our research is based on the smooth tube. A flow and heat transfer model has been developed to investigate the distribution of temperature and heat flux of the parabolic trough collector, and the influence of Reynolds number is also investigated. Secondly, an innovative inserted pin-fin arrays tube is introduced and investigated by building flow and heat transfer model. The influence of Reynolds number and distribution of fins on heat transfer and flow resistance characteristics are mainly investigated. The results show that the parabolic trough receiver with inserted pin-fin arrays tube has a significant ability of heat transfer augmentation. Compared to smooth tube, the inserted pin-fin arrays tube can rise the Nussult number for 6.6% and the overall heat transfer performance for 8%. Keywords: solar energy, heat flux distribution, thermal strain, heat transfer enhancement, inserted pin-fin arrays 不要删除行尾的分节符，此行不会被打印目 录 摘 要 I Abstract II 第1章 绪论 1 1.1 课题背景及研究意义 1 1.2 管式集热器的温度场及热应变研究现状 3 1.2.1 管式集热器的温度场研究现状 3 1.2.2 管式集热器的热应变特性研究现状 4 1.3 内翅片管换热器的研究现状 5 1.4 本文的主要研究内容 6 第2章 太阳能管式集热器内流动及换热模型 8 2.1 引言 8 2.2 模型建立 8 2.2.1 物理模型 8 2.2.2 数学模型 9 2.2.3 边界条件 14 2.2.4 udf编译 15 2.3 网格划分及无关性验证 17 2.3.1 网格