干涉型太阳选择性吸收涂层的光学性能设计

THE DESIGN ON SOLAR SELECTIVE ABSORBING SURFACE WITH INTERFERENCE EFFECT

利用等效媒质理论对铝复合单层膜的光学性能进行计算并以此为基础优化设计了具有干涉效应的铝复合选择性吸收涂层。该吸收层为两层时膜系光谱曲线具有最明显的干涉效应，与多层吸收层膜系相比其发射率低，吸收率二者相同，随温度的升高，发射率的变化前者较后者缓慢。实际制备了金属填充因子ｆＡｌ为０．３８、０．２４的铝复合膜为吸收层，ＡｌＮ、Ａｌ２Ｏ３为减反射膜构成的膜系，其光谱曲线与优化的理论曲线吻合较好。

An aluminium selective absorbing surface with two uniform cermet absorber layers has been designed using Effective Medium Theories.The reflectance spectrum of this surface has distinct interference peaks than that of the graded selective absorbing surface.The formet has lower emittance and the same absorptance as the latter.The emittance of the bisublayer cermet absorber increases slowly with increasing temperature.Optimum selective surface has been made with bisublayer cermet absorber,whose metal volume fraction are 0.38 and 0.24,and Al 2O 3、AlN antireflection layers.A good agreement has been achieved between the computed and experimentally measured reflectance.