真空玻璃盖板热管平板式太阳能热水器的理论与实验研究

【作者】 王世锋；

【导师】 胡亚才； 王建平； 洪荣华；

【作者基本信息】 浙江大学 ， 工程热物理， 2004， 硕士

【摘要】 真空玻璃盖板热管平板式太阳能集热器是由我们发明的一种新型太阳能集热装置。本文研究了由真空玻璃盖板热管平扳式集热器构成的分体式太阳能热水器的性能。文章首先对目前太阳能开发利用的特点和太阳能热水器的现状及发展趋势作了简要介绍，同时回顾了我国太阳能热水器的产业化发展情况，在此基础上提出了本文的研究课题。 本文提出的太阳能热水器最大的特点是同时应用了真空玻璃技术和热管技术的平板式太阳能热水器。重力热管具有的热二极管特性，并且具有较强的传热能力和较高的等温性，这使得热管在太阳能的热利用中得到应用。而在太阳能平板集热器的表面使用真空玻璃作为盖板，在对于太阳辐射吸收影响不大的情况下，可以大大降低盖板外表面的散热损失，可以显著提高集热器的热转换效率。 为了探讨真空玻璃盖板热管平板式太阳能热水器的性能，本文通过实验测量了各种天气状况下热水器的运行状况，得出了瞬时效率、日平均效率和热损系数等热性能数据，并与蜂窝热管平板式太阳能热水器和全玻璃真空管式太阳能热水器的热性能进行了比较。对三种太阳能热水器的日平均效率进行比较，在低温段(30—60℃)蜂窝热管平扳式太阳能热水器的日平均效率为0.525，真空玻璃热管平板式太阳能热水器的日平均效率为0.537，而全玻璃真空管式太阳能热水器的日平均效率仅为0.456，可以看出蜂窝和真空玻璃热管平板式太阳能热水器的日平均效率都比全玻璃真空管式太阳能热水器的日平均效率要高。在高温段(60—90℃)蜂窝热管平板式太阳能热水器的日平均效率为0.306，真空玻璃盖板热管平板式太阳能热水器的日平均效率为0.348，全玻璃真空管太阳能热水器的日平均效率为0.325。可以看出在高温段蜂窝热管平板式太阳能热水器的日平均效率比全玻璃真空管太阳能热水器的日平均效率要低，而真空玻璃盖板热管平板式太阳能热水器的日平均效率仍然比全玻璃真空管太阳能热水器的日平均效率要高。 对三种太阳能热水器的热损系数进行比较，在低温段(30—60℃)蜂窝热管平板式太阳能热水器的热损系数为1.11，全玻璃真空管式太阳能热水器的热损系数为1.64，而真空玻璃热管平板式太阳能热水器的热损系数为0.93。在高温段(60一90℃)蜂窝热管平板式太阳能热水器的热损系数为1.45，全玻璃真空管太阳能热水器的热损系数2.59，而真空玻璃盖板热管平板式太阳能热水器的热损系数仅为1 .08。 可以看出无论在低温段还是高温段，真空玻璃盖板热管平板式太阳能热水器的热损系数都比蜂窝热管平板式太阳能热水器和全玻璃真空管太阳能热水器的热损系数要低。这就进、一步从实验上证明了真空玻璃盖板热管平板式太阳能热水器应用了真空玻璃和热管技术后集热性能和保温性能都得到了显著的提高。更多还原

【Abstract】 Flat plate solar water heater of vacuum glass-cover board and heat pipe(abbreviated as HVGHP) is a new solar energy gather device of our invention. In the paper, the heat performance of HVGHP is studied. At first, actuality and development of solar water heater at domestic are analyzed and the development of our country’ s solar water heater industry are reviewed. Then the researching contents are put forward.The distinguishing feature of HVGHP is applying vacuum glass technology and heat pipe technology. A gravity heat pipe possesses heat diode characteristics and excellent transfer heat ability and equality temperature characteristics. And a vacuum glass-cover board can greatly reduce heat loss caused by surface convection, and hence a better transfer efficiency.Through experimentation, we compare the heat performance of HVGHP , the flat plate solar water of honeycomb and heat pipe (abbreviated as), and the solar water heater of glass vacuum tube (abbreviated as HGVT). The heat performance of a solar water heater includes instantaneous efficiency, average heat efficiency and heat loss coefficient. At low temperature (between 30C and 60C), the average heat efficiency of’HHCHP is 0. 525, that of HVGHP is 0. 537, and that of HGVT is 0. 456. We can see that the average heat efficiency of HVGHP is higher than that of HHCHP and HGVT. At high temperature(between 60C and 90C), the average heat efficiency of HHCHP is 0. 306, that of HVGHP is 0. 348, and that of HGVT is 0. 325. We can see that the average heat efficiency of HVGHP is higher than that of HGVT and that of HGVT is higher than that of HHCHP.At low temperature (between 30C and 60 C), the heat loss coefficient of HHCHP is 1. 11, that of HVGHP is 0.93, and that of HGVT is 1.64. Wecan see that the heat loss coefficient of HVGHP is higher than that of HHCHP and HGVT. At high temperature (between 60C and 90C), the heat loss coefficient of HHCHP is 1.45, that of HVGHP is 1.08, and that of HGVT is 2.59.We can see that whatever at low temperature or at high temperature, the the heat loss coefficient of HVGHP is lower than that of HGVT and that of HHCHP. Hence the experimentation proved that the heat performance of HVGHP is greatly improved by applying vacuum glass technology and heat pipe technology.更多还原