中文摘要：

抛物槽式系统中汇聚光线在腔体吸收器内的反射次数对黑腔性能有重要影响，为最大限度提升三角腔体吸收器的采光能力，建立与抛物镜面之间的光路方程，分析腔内二次反射临界条件下对应于不同开口角度的最优镜面设计参数。提出有效孔径比率用于衡量反射镜与腔体的匹配性，并针对实验用的聚光系统分别进行计算，结果表明：腔体开口角度为60°时，焦距为1150mm、孔径为2220m／lq的反射镜面有效孔径比率为0．95，而焦距为1000mm、孔径为3000mm的反射镜面有效孔径比率仅为0．61。基于TracePro模拟分析验证了有效孔径比率可用于衡量腔体安装位置对光学效率的影响程度，在槽式系统设计及优化过程中应给予重视。

英文摘要：

The effect of the reflection times of converging rays in cavity absorber of parabolic trough concentrator on blackbody performance is very important. In order to maximize the light-gathering ability of the triangular cavity absorber, the ray equation between parabolic trough reflector and the absorber was established to analyze the design parameter for optimal reflector corresponding different opening angles under the secondary reflection critical condition. The concept of effective aperture ratio was put forward to evaluate the matching performance between reflectors and cavities. The condenser systems using for experiment were calculated. The optimal reflector design parameters for different cavity opening angles were calculated and the results were presented. The results show that for a triangular cavity with an opening angle of 60°, the effective aperture ratio of reflector with focal length of 1150 mm and aperture of 2220 mm is 0.95, while it is only 0.61% for another reflector with 1000 mm focal length and 3000 mm aperture. Meanwhile, the simulation and analysis based on TracePro software confirm that the effective aperture ratio factor can be used to evaluate the influence of cavity position on optical efficiency and must be considered during the system design and optimizing process.