复合抛物面-渐开线聚光的闷晒式太阳能热水器

Novel integrated solar water heater with compound parabolic and involute concentrator

针对全玻璃真空管与平板太阳能热水器存在系统复杂、成本高、不易维护等缺点,以及传统闷晒式热水器存在集热效率低和热损失严重等问题,提出了一种集热效率高、热损失小、成本低的基于复合抛物面-渐开线聚光的闷晒式太阳能热水器。对复合抛物面、渐开线以及复合抛物面和渐开线二者结合的聚光器进行了优化设计,制作了与该聚光系统配套的带有选择性吸收涂层的集热器水箱。最后,搭建了闷晒式热水器系统并进行了集热性能测试。结果表明,当太阳辐照强度的平均值为800 W/m^2、周围环境的平均温度约为21℃时,闷晒式热水器可以将40L水从21℃加热至62.20℃,系统的瞬时效率截距为0.63,热损系数为10.40 W/(m^2·℃)。而传统黑色聚乙烯塑料袋闷晒式热水器的瞬时效率截距为0.31,热损系数为13.32 W/(m^2·℃),与其相比,本系统在集热效率和保温性能上有着明显的优势,完全能够满足人们的日常生活用热水,具有良好的市场前景。

A novel integrated solar water heater with compound parabolic and involute concentrator with high heat-collecting efficiency,low heat loss and low cost was introduced,aiming at such disadvantages of all-glass evacuated tubular and flat plate solar water heater as complex system,high cost and maintenance inconvenience and such problems of the conventional integral solar water heater as low heat-collecting efficiency and serious heat loss.The optimization design was done for the concentrator of the compound parabolic,involute and the combination of compound parabolic and involute.Then the heat collector tank with selective absorbing coating which is matched with the concentrator system was designed.Finally,the integral solar water heater system was set up and the test for the heat collecting performance was performed.The results show that when the average solar irradiation intensity is 800 W/m2 and the average temperature of the ambient environment is about 21℃,the integral solar water heater can heat 40 Lwater from 21 ℃to 62.20 ℃ with the cut length of efficiency of the system is 0.63 and the heat loss coefficient is 10.40 W/（m2·℃）.However,the cut length of efficiency of the traditional integral solar water heater with black polyethylene plastic bag is 0.31 and the heat loss coefficient is 13.32 W/（m2·℃）,compared to which,the proposed system has obvious advantage on heat collecting efficiency and thermal insulation properties.Therefore it can fully meet the demands of people for hot water for daily life with good market prospect.