Determinación in situ de la resistencia térmica de envolventes edilicias livianas bajo condiciones de funcionamiento libre

HONGN, MARCOS; FLORES LARSEN, SILVANA; GONZÁLEZ, SILVINA; CASTRO, NICOLÁS; JAIME, DARÍO

Mendoza

Congreso; IV Congreso Latinoamericano de Simulación de Edificios; 2019

Facultad de Ingeniería, Universidad Nacional de Cuyo

In recent years, buildings energy consumption has become a major global issue. In order to assess the actual energy performance of buildings, a reliable in-situ estimation of the thermal resistance of walls (R-value) is required. In conditioned buildings there are many well-known quasi-steady and dynamic methods o determine R-value. Nevertheless, in free-running buildings there is no much information about the usefulness of the different available methods, the required measuring periods, convergence, etc., especially in mild and warm climates where both, stable non-inverting heat flux and high thermal gradients, do not naturally occur. A quasi-steady method as ISO 9869, and a dynamic method as Pentaur (Anderlind) was analyzed in this work with the aim of to evaluate the thermal resistance in a light building envelope and for adverse and random measurement conditions. Both simulated and experimental data sets of surface temperatures and heat fluxes were used to analyze the effect of the measuring conditions (surface temperature difference and direction of the heat flow) on the convergence and final R-values. The results indicated that the Pentaur method allows determining the R-values with accuracy, for the differents year stations. This research provides guidelines to employ the Pentaur method and the required survey duration for in-situ estimation of the thermal resistance in free-running buildings.