Ray-tracing software comparison for linear focusing solar collectors

Abstract

Abstract. Ray-Tracing software tools have been widely used in the optical design of solar concentrating collectors. In spite of the ability of these tools to assess the geometrical and material aspects impacting the optical performance of concentrators, their use in combination with experimental measurements in the framework of collector testing procedures as not been implemented, to the date, in none of the current solar collector testing standards. In the latest revision of ISO9806 an effort was made to include linear focusing concentrating collectors but some practical and theoretical difficulties emerged. A Ray-Tracing analysis could provide important contributions to overcome these issues, complementing the experimental results obtained through thermal testing and allowing the achievement of more thorough testing outputs with lower experimental requirements. In order to evaluate different available software tools a comparison study was conducted. Taking as representative technologies for line-focus concentrators the Parabolic Trough Collector and the Linear Fresnel Reflector Collector, two exemplary cases with predefined conditions -geometry, sun model and material properties -were simulated with different software tools. This work was carried out within IEA/SHC Task 49 "Solar Heat Integration in Industrial Processes".

IEA SHC Task 49/IV - Deliverable A3.1 - Guideline on testing procedures for collectors used in solar process heat

“…To better understand these questions, a comparison of different ray tracing software solutions was performed within the work of IEA Task 49, its results are currently under publication (Osório et al 2015 Table 11: Participants software tools and performed simulations (Osório et al 2015), *copy available on licensefee…”

Time-Resolved Temperature Map Prediction of Concentration Photovoltaics Systems by Means of Coupled Ray Tracing Flux Analysis and Thermal Quadrupoles Modelling

“…Nevertheless, as stated in [34] (p. 020017-5), "…to model a refractive component on Tonatiuh one has to define two refractive surfaces with coefficients to the transmission, absorption, reflection and refractive index at each side". This approach has been implemented successfully for this work.…”

OTSun, a python package for the optical analysis of solar-thermal collectors and photovoltaic cells with arbitrary geometry

“…On the one hand, we cover the absence of open source software that is focused on both solar technologies (thermal and photovoltaic). On the second hand, we implement the Fresnel equations in their most general form, without further simplifications, avoiding the aforementioned problem reported in [7]. The OTSun package uses FreeCAD [17], a free 3D CAD system, in order to model the geometry of the optical systems to be analyzed, and also uses its API to compute the intersections of rays with the scene .…”

“…At present, only three of them, Tonatiuh [ 4 ], HOpS [ 5 ] and SolTrace [ 6 ], are licensed as open source. Another recent study focused in solar thermal applications was realized in the context of IEA/SHC Task 49 “Solar Heat Integration in Industrial Processes” [ 7 ], where a round-robin ray tracing software comparison for Linear Focusing Solar Collectors (LFSC) was done. In this study, the main differences between the software packages under study were found in how they model the angular dependency of the optical properties of the materials.…”