A ANÁLISE DE SENSIBILIDADE DO POC EM EDIFICAÇÕES NATURALMENTE VENTILADAS

Abstract

The thermal performance of buildings with natural conditioning -or that do not consume energy to modify the internal thermal conditions of a building - employs environmental variables of thermal comfort, that can be estimated by building performance simulation. The adaptive comfort methodology proposed by the ASHRAE 55 standard considers temperature as a prime factor for determining the acceptability of the user's thermal comfort for a given climate and building, thus allowing designers to verify that a design is capable of providing thermal comfort during the different seasons of the year. Therefore, for a previously modeled building in which the characteristics of the construction systems could vary, it was proposed a simulation of the thermal performance using the natural ventilation using weather files previously developed for the city of Viçosa-MG, Brazil. Then, an analysis compared methods of selection of the representative climatic year for thermal comfort conditions, in order to point out the most reliable for the Brazilian climate. Energyplus was used to describe ad simulate the characteristics of the construction systems and the proposed natural conditioning systems. Weather files developed from the same database were compared using some of the methods used by the cited author: the two main methods used in Brazil, TRY and the Brazilian TMY; a method used in the USA, TMY3; the most widely used method in Europe, the European TRY; the 3 multiyear method, in which a reference year was identified with the lowest values of temperature and radiation, another year with the highest values of temperatures and radiation, and one year with mean values for the same parameters; and lastly the 10 multiyear, in which the data for each of the 10 years of climate data, collected for the city of Viçosa-MG, were analyzed. As indicated by previous studies that TMY3 was the most suitable synthetic format for conditioned buildings, this study confirms its use for naturally ventilated buildings, as it shows how TMY3 best describes the time series with a single format.