平板型太阳能聚光器的无漏光设计

针对平板型太阳能聚光器中出现的漏光问题,提出了无漏光聚光器的设计方法.该方法结合简单的数学计算与折射定律、反射定律推导出光线在光波导板中无漏光传播的最大距离理论公式,建立了无漏光聚光比与空气隙结构张角角度、主聚光器高度和宽度之间的数学模型,利用控制变量法分析了无漏光聚光比与各参数之间的关系.运用光线追迹软件对所设计的平板型无漏光太阳能聚光器进行光线追迹模拟,结果表明:在模拟光源选择存在0.27°的发散半角的太阳光源条件下,考虑光线在透射面处的菲涅耳损失和光学材料的吸收,在无漏光范围内实际最大聚光比达到698×、857×和1 032×时的聚光效率分别为88.2%、85.3%和80.2%;超过无漏光范围后随着聚光比进一步增大聚光效率下降较平缓.

Design and Analysis of Planar Solar Concentrator in Ray-leakage-free Respect

Planar solar concentrator can provide dynamic concentration ratio,which has attracted researchers' attention.However,the decrease of the optical efficiency is not improved because of the raysleakage from the lightguide.In order to hinder the decrease of optical efficiency from ray leakage,a new design method of the ray-leakage-free planar solar concentrator is proposed in this paper.According to the mathematical computation,refraction law and reflection law,the theoretical formula of the maximal rayleakage-free propagating length in lightguide is derived.Furthermore,the mathematical model among the values of the parabola arbitrary coefficient,the vertex angle of air gap structure,the collector width,the collector height and the ray-leakage-free concentration ratio is established.The model of the proposed rayleakage-free planar solar concentrator is simulated by the ray-tracing software.In consideration of Fresnel loss and material absorption,the concentration ratios of the proposed concentrators reach 698 ×,857 ×and 1 032× with the corresponding optical efficiencies 88.2％,85.3％ and 80.2％,respectively,when the sunlight possess 0.27° divergence half angle;the concentration ratio increases further while the optical efficiency decreases slowly when the length of the lightguide exceeds the ray-leakage-free range.