【作者】 陈宇；

【导师】 代彦军；

【作者基本信息】 上海交通大学 ， 供热、供燃气、通风及空气， 2012， 硕士

【摘要】 本文针对太阳能中温集热技术和应用需求,围绕菲涅尔线聚焦集热器以及蓄热装置进行研究。论文设计构建了一种线聚焦菲涅尔太阳能集热器,分析了菲涅尔线聚焦集热器热损失系数以及集热效率。利用Tracepro计算表明,所研究的菲涅尔线聚焦集热器最大光学效率为75.5%;针对此类集热器建立了菲涅尔柱面镜的光线踪迹法模型,得到柱面镜宽度、吸收器高度、光斑宽度、光斑能量密度分布之间的优化关系;搭建了14.4m2菲涅尔线聚焦集热器测试平台,测试实际光学效率为55.7%,150℃时的集热效率为36.6%,单位长度吸收器热损失系数为110.0W/m。论文还针对集热温度在80～250℃之间的蓄热需求,研究了包括石英砂与钢砂混合材料显热蓄热、KNO₃/LiNO₃共晶盐、季戊四醇（PE）/三羟基乙烷（PG）固固相变材料等,其中利用成型膨胀石墨制取PE/PG复合材料使其导热性能增加6倍以上。考虑加工工艺等问题,采用石英砂和钢砂的混合材料作为蓄能材料,结合蛇形盘管换热器设计加工了2kWh的蓄能装置,并连接菲涅尔与槽式集热器进行测试。以火用效率、热效率以及集热效率为指标,建立相应模型得到以下结论:集热蓄能装置充放热的综合热效率为81.3%,火用效率为52.3%,蓄热体积与集热器面积之比在80L/m2时为最优值。上述结论对于工业中太阳能中高温应用具有指导价值。更多还原

【Abstract】 In this paper, for the solar medium temperature thermal technology, Linear Fresnel lens solar collector and thermal storage were studied. A linear Fresnel collector was designed and established. Then, the optical, heat loss and thermal efficiency of Fresnel lens collector were defined, and the maximum of optical efficiency was 75.5% by Trace-pro optical software. Meanwhile, the light trace of Fresnel lens mirror was modeled, the optimized relation of mirror’s width, receiver’s height, beam’s width and energy density were studied. Then, The 14.4m2 prototype of Fresnel lens solar collector was established, the test result showed that the practical optical efficiency is 55.7%, the efficiency of collector is 36.6% at 150℃and the heat loss of the receiver is 110.0w/m。Furthermore, in order to find a suitable the thermal storage for medium temperature solar collector, mixture material of quartz sand and steel shot , KNO₃/LiNO₃ molten salt and solid phase change material were studied. Then, a composite material comprised of solid phase change material and expanded graphite was developed and its heat conductivity was increased 6 times. Finally, a 2kWh sensible thermal storage which is combined with serpentine heat exchangers was established. According to the thermal efficiency, exergy efficiency and collector efficiency, the results showed that the thermal efficiency of heat storage is about 81.3%, exergy efficiency is about 51.3%, The optimized thermal storage volume-to-parabolic trough collector area ration is 80L/m2 by coupled heat transfer model, and the desired heat transfer area could reduce a lot when the heat conductivity increases to 2.0 W/（m·℃）. The solar indutrail thermal application could benefit from the above conclusion.更多还原