ASSESSMENT OF THE THERMAL PERFORMANCE OF A PARABOLIC SOLAR STOVE

Abstract

This article evaluates the thermal performance of a parabolic solar stove prototype to which technological improvements were introduced. The prototype includes a 1.28 m diameter parabolic dish and a ¾-inch square steel profile frame. To increase the thermal performance of the stove, a polyethylene terephthalate self-adhesive reflective film was included with a reflectivity factor of 95% on the paraboloid, increasing the solar irradiation directed to the focus of the parabola. Additionally, the steel container used for cooking in the stove, with a volumetric capacity of 3 liters, was covered with a matt black high-temperature paint with an absorptivity of 95%, to increase heat transfer. Twelve 2-hour experimental tests were developed over 8 days in the suburban area of ​​the city of Pereira between 10:00 a.m. and 4:00 p.m., which is the period of the day where there are adequate solar irradiation conditions for cooking on the stove. To calculate the thermal efficiency of the system, temperatures and solar irradiation were measured every 5 minutes using a TP-101 thermometer for the water in the cooking container, a Flir One thermographic camera for the pot surface and a LI-200R pyranometer. for global irradiation. The results show that the efficiency of the stove varies between 35% and 51% for the measured solar irradiation conditions.