Thermal behavior of building walls in summer: Comparison of available analytical methods and experimental results for a case study

Abstract

There is a wide variety of thermal analyses that can be used to characterize the thermal behavior of a wall under certain outdoor conditions. The selection of a particular wall configuration for a building project involves not only the outdoor climate, but also the whole building characteristics, orientation, percentage of glazed areas, occupation periods, lifestyles, etc. In this paper we apply common available methods for wall thermal analysis to two particular wall types, a massive brick wall and an insulated brick wall, in order to compare the information given by each method and to evaluate how these methods can help in the selection of a certain type of wall. The studied methods include the estimation of the wall time lag and decrement factor, the harmonically heated slab model, the Athanassouli's method, and numerical simulations. The study was performed for the walls of a residence for university students and it was built in La Pampa (Argentina). Once the building was finished, the transient thermal behavior of two walls was monitored during one summer week. The experimental results are presented and the fitting with the thermal behavior predicted by each method is discussed. The thermal comfort indicators PMV (predicted mean vote) and PPD (predicted percentage of dissatisfied) were calculated for two flats, at ground floor and first floor respectively.

Seasonal and Diurnal Characteristics of Land Surface Temperature and Major Explanatory Factors in Harris County, Texas

“…Previous research has concentrated primarily on biophysical and meteorological factors determining LST in the urban environments. Building envelopes are known to be a dominant factor in the energy consumption of buildings [35], thus it is likely that wall and roof types with different thermal behaviors will also impact outdoor thermal environments. While the effects of building morphology have been studied with respect to ventilation and UHI development, there has been almost no research on how building wall characteristics influence LST intensity within a big city.…”

Development of an Optimal/Robust Control Strategy for Electrical Energy Cost Minimization in an Air-Conditioning Plant

“…Therefore the thermal resistance for conduction for each side of the wall can be defined as (3) where R w is the total thermal resistance of the wall, which can be expressed as (4) Where L is the thickness of the wall, k is the thermal conductivity of the wall material, and A is the area of the wall. the convective heat transfer coefficient (h) depends on the type of fluid, flow properties and temperature properties, it will have different values for the two sides of the walls depending on the factors mentioned above for each side [3]. For simplicity, we only consider two different convective heat transfer coefficients, one for the internal and one for the external sides of the peripheral walls.…”

Współczynnik Tłumienia Amplitudy Wahań Temperatury Izolacji Termicznej Modyfikowanej Materiałem Fazowo Zmiennym

“…Wpływ wła-ściwości fizycznych materiałów oraz absorpcyjności promieniowania słonecz-nego zewnętrznej powierzchni przegrody na wartość współczynnika tłumienia został opisana w literaturze [5,6]. Wartość współczynnika tłumienia może być wyznaczona dla rzeczywistych warunków klimatycznych [7] lub uśrednionych sinusoidalnych przebiegów zmian temperatury.…”