Estudo sobre refrigeração passiva usando spray d'água em telhado composto por telhas de fibrocimento

Abstract

The present work aims to study the effects of water spraying and consequent evaporation on the roof of a laboratory with fiber cement roofing tiles, with the purpose of reducing heat transfer to the interior of the building. This study was made using theoretical models proposed through energy balances in the control volume of each roof surface, for later equationing of the problem. Following the formulation, two computational codes were developed in the Engineering Equation Solver platform to solve through interactions between the models, one without spraying water and one spraying. The results were evaluated for the case in question with air temperature at 30ºC and laboratory internal temperature at 28°C and for some variations of internal temperature of the laboratory and absorption of the roof material. The results are presented in the form of graphs and, to serve as references in the future, in the form of tables. This allows a greater variation in the analysis of the effects of water evaporation on the reduction of the temperature of the roof and the consequent improvement in the comfort of the environment. It is also discussed the possibility of other improvements such as: decrease of water waste through the reuse of non-evaporated water, with a collection system integrated to the feed tank. Also, as an improvement in energy efficiency, a control system could be proposed for the activation of the water sprinkler as a function of roof temperatures. Such a system could be implemented in the future.