针对槽式聚光系统,设计了一种倒梯形管簇式腔体接收器,采用理论研究、TracePro软件模拟以及实验的方法对腔体结构设计中某些几何参数对接收器的光学性能的影响进行分析及优化,并对其安装位置偏移对光学性能的影响展开研究。结果表明:倒梯形上壁面为弧面反射面可使光学效率提高近4%;随着开口角度增大光学效率逐渐增大,随着圆弧半径增大光学效率先增大后缓慢降低,开口角度65°与反射圆弧半径90 mm的组合结构具有较高的光学效率、较均匀的集热管壁能流以及较好的光热转化效率;腔体接收器安装在焦距垂直向下5 mm范围内可获得优于焦距处的光学效率;运用归一化温差和测试瞬时集热效率的方法得到槽式聚光集热系统的光学效率为73%,与模拟的理想值较吻合。

A new inverted trapezoidal cavity receiver with absorber of a bundle of tubes used in trough solar concentrator system is designed. The influence of some geometric parameters in the cavity design on the optical performance of the receiver are theoretically analyzed and optimized by theoretical analysis, Tracepro software simulation and experimental methods. Furthermore, the influence of installation position deviations on optical performance of the cavity receiver are studied. Simulation and analysis results show that the wall surface on inverted trapezoid is reflex arc surface, whose optical efficiency can be improved nearly 4%. The optical efficiency increases gradually with the increase of opening angle, and firstly increases and then decreases slowly with the increase of arc radius. The combination of the opening angle of 65° and the radius of the reflection arc 90 mm has higher optical efficiency, more uniform energy flux distribution on the wall of collector tube, and better photothermal transfer efficiency. When vertical installation position is 5 mm below focal length, the optical efficiency is better than that at the focal length. By using the normalized temperature difference and the test method of the instantaneous heat collection efficiency, the optical efficiency of the trough concentrating collector is 73%, which is in good agreement with the ideal value of the simulation.