Optical Raytracing Analysis of a Scheffler Type Concentrator

Year: 2022

Authors: Fontani D., Sansoni P., Francini F., Toni F., Jafrancesco D.

Autors Affiliation: National Research Council-National Institute of Optics (CNR-INO), 50125 Florence, Italy

Abstract: The Scheffler type concentrator is a curved metal reflector particularly suitable for solar
thermal systems with a receiver fixed to the ground. Its operating principle is to deform the reflector
throughout the year to optimize its performance in collecting sunlight. This study analyses the optical
performance of a Scheffler reflector during the year. A CAD software tool is utilized to reproduce
the mechanical deformations of a real Scheffler concentrator and the shape of the light spot on the
receiver is analyzed by means of raytracing simulations. The starting configuration is the equinoctial
paraboloid, which produces a point-like spot on the two equinox days only. On all other days of the
year, this paraboloid is deformed in a suitable way in order to keep the spot as small as possible, but,
even so, it is no longer a point-like spot. In the present work the simulated light distributions on the
receiver, generated by the paraboloids (deformed or original), are compared. The results confirm the
working principle of the Scheffler type concentrator and allow correctly sizing the receiver.

Journal/Review: ENERGIES

Volume: 15      Pages from: 260-1  to: 260-20

KeyWords: solar concentration; optical design; Scheffler concentrator; 3D CAD simulation; optical analysis; thermal application
DOI: 10.3390/en15010260