Optical Performance Assessment of a Solar Collector with a Static Concentrator

J. Goettsche1, S. Alexopoulos1, A. Dümmler1, G. Breitbach1
1FH Aachen, Solar-Institut Jülich, Germany
Published in 2020

In this paper a specific version of radiation collecting troughs is investigated. The trough arrangement has a shape which is a combination of a circular arc and adjacent parabolic curve pieces based on a paper by Tripanagnostopoulos [1]. An absorbing tube can be placed at varying positions depending on the solar incidence angle. It is investigated how the absorbed solar radiation depends on tube for different incident angles. The analysis consists of different steps. Using MATLAB the reflection of parallel entering ray bundles are investigated. This first step gave a first insight into the distribution of rays. Zones inside the trough are identified where reflected rays concentrate.
Holding the trough fixed optimal positions for the tube move along an inclined line. Then a detailed ray tracing analysis was done with the COMSOL software. COMSOL contains powerful tools (geometrical optics) to follows the rays through tranparent media with reflecting and absorbing boundaries. Using 2-D models the distribution of the radiation fluxes along the tube surface and along an enclosing envelope were calculated. For different incident angles results are presented giving the radiation fluxes in detail.
The work was carried out as part of the project ScoSco funded by the German Federal Ministry of Education and Research.