全玻璃真空集热管热损系数的理论计算和实验

Theoretical Calculation and Experimental Research on Heat Loss Coefficient of All Glass Evacuated Tubular Collectors

本文根据热网络法原理,运用电子计算机计算了不同工况下全玻璃真空集热管加涂不同选择性吸收涂层的热损系数;应用非稳态卡计法原理,提出了热损系数的测试方法和计算公式,实测结果与理论计算相符,表明该方法简便、快速和可靠。最后提出了工程上应用性较强的热损系数经验计算公式。

According to the principle of heat net method,heat loss coefficients of allglass evacuated tubular collectors coated with four kinds of selective absorptivecoatings were calculated by using an electronic computer.By means of the transientcalorimetric method,a new measuring method and a formula for calculating heatloss coefficients were presented.Those values thus measured accorded with theore-tical calculated results,so the new transient measuring method was quick,handyand reliable.At the end of this paper,an experimental formula available in engi-neering applications for calculating heat loss coefficients was given.