Mostrando artículos por etiqueta: HoSIER publication
Assesment of a Polymeric Reflective Coating for High Concentration Point Focus Applications
D. Riveros-Rosas, R. Castrejón-García, C. A. Arancibia-Bulnes, C. A. Pérez-Rábago, C. A. Estrada-Gasca
Abstract
A methodology for the evaluation of the specularity error of a polymeric filmoptical coating is presented. The methodology is based on the comparison of images from the sun produced by two high quality spherical mirrors, one covered with a highly specular evaporated aluminumfilm, and the second one with the polymeric film under study. This film is a commercial product known as Reflectech®. To determine the specularity error, both images are reproduced by means of ray tracing optical simulations. Those simulations use the angular brightness distribution from the sun as input, which were recorded by means of a specially developed solar scope. Significant differences are obtained between images of the sun generated by both mirrors. However, the specularity error of the coating under consideration is found to be just 0.71 mrad. This error is quite small making the polymeric coating highly appropriate for point focus concentration systems. This is illustrated by calculations for a parabolic dish concentrator.
Assesment of a Polymeric Reflective Coating for High Concentration Point Focus Applications
Correction of the concentrated sunlight spot´s drift of the IER-UNAM´s solar furnace
R. Pérez-Enciso, E. Brito-Bazan, C.A. Pérez-Rábago, C.A. Arancibia-Bulnes, D. Riveros-Rosas, C.A. Estrada.
Abstract
This paper discusses the methods implemented for the solution of the drift and backlash problems in the heliostat of the High Radiative Flux Solar Furnace recently built at the Renewable Energy Institute (former Center for Energy Research) of the National University of Mexico (IER-UNAM), located at the geographical coordinates 18°50′24″ North latitude and 99°15′00″ West longitude. To solve the observed drift, several algorithms were analyzed for the calculation of the solar vector, and a closed loop through an electronic device (peephole) was implemented which makes corrections to the position of the heliostat. Using the peephole, drift heliostat decreased significantly; 70% in the horizontal direction and 63% in the vertical direction relative to the no use of peephole. The backlash was corrected by means of unbalancing the heliostat.
Correction of the concentrated sunlight spot´s drift of the IER-UNAM´s solar furnace
