针对腔体吸收器安装位置对其光热转换性能的影响进行了理论、模拟、实验研究。构建了太阳能槽式系统吸收器表面辐射热损失的物理模型，并进行了数学验证，结果表明吸收器表面的辐照度趋于均匀分布时，系统的热辐射损失减小。基于TracePro软件模拟了腔体吸收器在不同位置时的光学效率、辐照度标准差，发现腔体吸收器安装位置小于焦距时可获得较好的光学性能，采用焦距为1200 mm的槽式系统进行了腔体吸收器光热转换性能的实验验证，当腔体吸收器安装焦距为系统焦距的98.75%，集热温度为201.3 ℃时，所构建的槽式系统的热效率可达35.53%。

The photo-thermal conversion characteristic of cavity absorber in parabolic trough solar concentrator is researched by theory, simulation and experiment. The thermal radiation loss model of cavity absorber in parabolic trough solar concentrator is established and demonstrated. Results show that while the irradiance distribution of cavity tends to be uniformity, the thermal radiation loss is reduced. The optical efficiency and standard deviation of cavity absorber at different positions are simulated by the optical design software TracePro. Results show that better optical performance can be obtained if the installed position is less than the focal length. The thermal efficiency of the cavity absorber is 35.53% with the temperature of 201.3 ℃ and the installed focal length of cavity absorber is 98.75% of system focal length which is 1200 mm parabolic trough solar concentrator by experimental verification.