Thermal-mechanical performance analysis of parabolic trough receivers under various optical errors based on coupled optical-thermal-stress model

Abstract

As green and sustainable technology, the parabolic trough receiver's thermal-mechanical performance is widely concerned because of the optical errors in all practical systems. The coupled MCRT-FVM-FEM approach was employed to construct the receiver's optical-thermal-stress model. The receiver's safety and thermal-mechanical performance is thoroughly analyzed using the model to illustrate the coupling effects of tracking error (σt), slope error (σs), and installation error (σx and σy). Bellows and Kovar ring's deformation and thermal stresses under multi-error are investigated for the first time. Bellows and Kovar rings' variable expansion and uneven axial stresses are brought on by the uneven heat flux distribution and absorber's heat transfer. While bellows and Kovar ring enhance absorber's deformation and stress. Optical errors mainly affect the bellow's axial tensile stress and the Kovar ring's axial compressive stress. Tracking and installation errors have less impact on receiver safety when σs exceeds 4 mrad. However, they enhance the risk of receiver failure when σs is sufficiently small (<4 mrad). Positive σy leads to receiver's maximum deformation (23.57 mm), significantly increasing the Kovar ring's maximum compressive stress and threatening the receiver's safety. Therefore, the impact of bellows and Kovar ring on receiver safety should be considered when simulating actual operation.