Simulation and optimization of parabolic trough receiver with non-uniform heat flux distribution: A review

The parabolic trough collector (PTC) is the most mature and commercially tested technology among concentrating solar power technologies. In the concentration process of sunrays, non-uniform heat flux distribution (NUHF) forms outside the absorber tube. As a result, temperature gradients and temperature peaks in the absorber tube emerge, which bring challenges to the efficiency and reliability of parabolic trough receivers (PTRs). This work presents a brief overview of researches on NUHF of PTCs, including the calculation methods of NUHF, simulation studies of PTRs and various optimization methods of NUHF. For solutions to NUHF, there are no set standards available for comparison and selection of them. More efforts are needed for theoretical studies to avoid repeated works and for economic studies to justify these optimization methods. (C) 2017 The Authors. Published by Elsevier Ltd.