毕业设计（文）-槽式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.doc

哈尔滨工业大学工学硕士学位论文哈尔滨工业大学毕业设计（论文）- PAGE II -- PAGE II -摘 要太阳能光热利用主要有无污染、零排放、不使用传统化石燃料的优点，其主要有槽式、塔式、碟式和线性菲涅尔式四种。目前槽式太阳能热发电系统已经在成熟的商业化应用中，但是，槽式太阳能热发电系统中的管式集热器在运行过程中，存在着换热效率低，温度场分布不均匀，换热温差大等问题。为了强化管式集热器的换热、均匀化集热器的温度场，提高系统利用效率，本文引入内置扰流柱群管作为抛物槽式太阳能热发电系统的集热器。本文首先以圆管式太阳能集热器为研究对象，建立太阳能槽式热发电系统中集热器的流动传热模型，对管式集热器表面的温度分布特性，热流分布特性进行分析，研究雷诺数对圆管式太阳能集热器的温度分布特性，流动与传热特性的影响规律；其次，引入内置扰流柱群管式太阳能集热器，建立内置扰流柱群管式太阳能集热器的流动传热模型，对内置扰流柱群管式集热器的传热特性及流阻特性进行数值研究，着重分析扰流柱分布特性和雷诺数对内置扰流柱群管式集热器的传热和流阻特性的影响。研究结果表明，内置扰流柱群管式太阳能集热器具有明显的强化传热性能，与圆管式太阳能集热器相比，其努塞尔数最多提高6.6%，此时的综合传热因子提高8%，集热器温度场分布更加均匀。关键词：太阳能；热流分布；强化传热；温度场；热应力；内翅片管AbstractThere 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