A novel CSP receiver based on airlight energy technology - optimization of the thermal insulation system by means of CFD analysis

The thermal behavior of the novel CSP receiver based on Airlight Energy technology was analyzed by means of accurate 2D steady-state computational fluid dynamics (CFD) simulations. Afterwards, its thermal insulation design was numerically optimized with the aim of minimizing the heat losses. Energy and radiation transport equations were numerically solved, using the finite-volume method approach, with Fluent code from ANSYS. In this innovative receiver design, air is used as heat transfer fluid (HTF) allowing to go beyond the operating temperature limits of conventional HTFs. However, air receivers need a larger heat transfer area and flow cross-section compared to the most common oil and molten salts receivers. Thus, the insulation becomes technically challenging. Due to a large thermal capacity, the use of conventional insulating material is not the best solution for air-based receivers. Instead, thanks to the advantages offered, thermal radiation shields were selected as main receiver insulation system. The analysis of the CFD simulations results drove the various modifications of the thermal insulation design; hence, a total of three versions were studied achieving, at the end, the final optimized solution which is implemented in the first full-scale 3.9 MWth pilot plant under construction in Ait Baha (Morocco). (C) 2013 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).