Damage Analysis of CSP Parabolic trough Heat Collector Element for Efficiency Improvement

Heat collector elements are a key component of CSP parabolic troughs. They play a vital role in the optimal operation of any solar power plant. In fact, any problem related to these absorbers decreases the efficiency and performance of the entire production plant. Starting early winter, a high number of HCEs were damaged in Noor 1 plant. The objective of this work is to conduct an analysis of CSP parabolic trough HCEs in order to investigate their damage, and find a solution to that. In fact, the damage of heat collector elements may be due to several causes, either design related or operational mistakes. Most of these problems lead to a more concrete and narrowed problem, which is the loss of vacuum in the annulus zone. This project involves four principal milestones. The first milestone consists of analyzing all possible design related causes leading to HCE damage; mainly glass-to-metal seal breakage, HTF cracking, glass permeability, and shield diffusivity. The second milestone entangles some of the possible operational problems, principally observed in Noor power station. The third milestone is devoted to a detailed, coupled numerical analysis of the effects of vacuum loss using ANSYS software. This later analysis is conducted in two main steps; first a CFD conjugate heat transfer analysis, followed by a Static Structural analysis. Finally, the fourth milestone involves a solution design suggestion to encounter the damage problem. The analysis conducted in this project proved our theory that when vacuum is lost in the annulus part, the glass casing of HCE breaks. Thus, the solution suggested in this project is the implementation of a dynamic vacuum design.