Comparative Study on Heat Flux and Temperature Distribution Performance of Linear Fresnel Collector Based on Uniformity Index

Linear Fresnel collector system as main solar energy collecting technology is widely studied. The secondary reflector has significant influence on the heat flux distribution on the linear Fresnel collector. In this work, the heat flux and temperature distribution on linear Fresnel collector is compared with different secondary reflectors of simple trapezoidal concentrator, segmented parabolic concentrator and compound parabolic concentrator under varied incident ray angle. The uniformity index is applied to evaluate the Linear Fresnel reflector system heat flux distribution performance. The results show that the value of uniformity index increases with the increasing of incident ray angle. The compound parabolic concentrator has the highest value of uniformity index compared with simple trapezoidal concentrator and segmented parabolic concentrator in this work. The highest value of uniformity index is 0.8137 with compound parabolic concentrator. This work provides effective and practical guide to design and evaluate the secondary reflector in linear Fresnel reflector system.