Comparison of Dynamic Data Analysis Methods for Thermal Property Measurement of a Building Wall

Abstract

Energy usage in heating and air-conditioning a building is influenced by several factors. Among them is the building wall, whose production is affected by the planning, design and construction process. This process causes a certain deviation of the theoretical and actual values of the building wall's thermal transmittance. For constructed buildings, if the thermal properties of the building wall, on site, are calculated rapidly and accurately, it will make the testing process easier and the analytical results more accurate. In this paper, two methods for analyzing the building wall's thermal transmittance, where data is measured on site, are presented. They are respectively called the dynamic analysis method and the system identification method. The two methods are based on two different thermal models. Both models of the wall's heat transfer were solved with the system identification algorithm. Analysis and comparison of the two methods shows that the system identification method for analyzing the measured dynamic data is simpler and has a shorter measured time.