量热法SS-AlN太阳吸收涂层半球发射比测量装置

AN APPARATUS FOR MEASURING HEMISPHERICAL EMITTANCE OF SS-AlN SOLAR ABSORBING COATINGS USING A CALORIMETRIC TECHNIQUE

采用稳态量热法,研制了一台真空集热管内管外表面SS-AlN太阳吸收涂层半球发射比测量装置。集热管内置三段式加热器,采用直流电源给加热器供电,测量在恒定温度时主加热器的加热功率,计算得到该温度下吸收涂层的半球发射比。多次测量同一支SS-AlN集热管的选择性吸收涂层的80℃半球发射比εss-AlN(80℃)=0.0596±0.0004。另外,多次测量同一支Cu真空管的Cu涂层的半球发射比εCu(80℃)=0.0217±0.0002。采用该装置测量真空集热管的吸收涂层半球发射比,测量精度高。

An apparatus for measuring hemispherical emittance of SS-A1N solar absorbing coatings using a calorim- etric technique has been laboratory-made. Three heaters, spaced by 3mm ceramic rings, heated with DC power supplies, were inserted inside the SS-A1N vacuum collector tube. Measuring the power dissipated in the central heater at the constant temperature for a vacuum solar collector tube, thus hemispherical emittance of the solar coat- ing on the outside surface of an inner tube may be calculated. The hemispherical emittance of the SS-A1N solar absorbing coating of a vacuum tube at 80℃ was measured for several times, the measured value of εss-AIN（80℃） is 0. 0596 ± 0. 0004. In addition, the hemispherical emittance of the copper coating of a vacuum tube at 80℃ was measured, the measured value of εCu（80℃） is 0. 0217± 0. 0002. The measured hemispherical emittance values with high precision have been achieved using this apparatus.