thermal resistance

Time lags and decrement factors for multi-layer materials without air gaps under air-conditioned and free floating conditions were obtained using the response factor and finite volume methods. The definitions under free floating conditions, which are independent of the external environmental conditions, are proposed for the first time. A special version of the finite volume method was employed in which the surfaces of materials were used as computational nodes and temperatures and heat fluxes on surfaces as primitive (state) variables.

Solar chimneys may provide enough ventilation to buildings when properly designed. Although many design tools, theoretical models and experimental studies have been reported, the impact of many design parameters such as the construction thickness, the thermal resistance of the walls, the absorptivity of the internal surfaces of the chimney, the thermal mass of the chimney and the type of glazing, is not well known. This paper aims to provide information on the optimum sizing of the above parameters.

The R-values of permeable insulation systems are generally determined in test apparatus designed to assure one-dimensional heat transfer and to assure no air intrusion effects. Such classical R-values are used to help describe insitu heat-tra