Thermal behaviour of open structures roofed with different types of single or multi-layer materials was investigated to evaluate their suitability for animals in hot climates. Outside and inside temperature of structure layers was recorded, as well as air temperature, direct and diffuse solar radiation. A simulation software called TRANSINUS has been developed for estimating interior surface temperature and inner air temperatures. It solves the Fourier’s differential equation into a system of finite difference equations depending on time. It takes into account the net radiant heat emitted from each interior surface of the structure. The ‘grey body’ theory was applied to a close cavity: involving the view factors and its reciprocal theorem, a system of equation was derived and solved to find out the net radiant heat. This simulation software predicts the thermal behaviour of roofed open or closed structure: thus, under a specific purpose such as well-being of animals, light weight or low cost materials, the more suitable solution can be chosen. Simulated and experimental data fit well, although the software requires simple input values. Test performed on different types of roof materials show that composite roof, such as thin water-proof layer coupled with insulating material, has a better thermal behaviour respect to single-layer material. Moreover, insulating materials can be substituted by air space between two layers. Wooden layer was investigated as interior surface showing a good performance and an excellent pleasure at sight.
A transient heat conduction model to simulate thermal behaviour of roofs and walls in hot climates
BIBBIANI, CARLO
2004-01-01
Abstract
Thermal behaviour of open structures roofed with different types of single or multi-layer materials was investigated to evaluate their suitability for animals in hot climates. Outside and inside temperature of structure layers was recorded, as well as air temperature, direct and diffuse solar radiation. A simulation software called TRANSINUS has been developed for estimating interior surface temperature and inner air temperatures. It solves the Fourier’s differential equation into a system of finite difference equations depending on time. It takes into account the net radiant heat emitted from each interior surface of the structure. The ‘grey body’ theory was applied to a close cavity: involving the view factors and its reciprocal theorem, a system of equation was derived and solved to find out the net radiant heat. This simulation software predicts the thermal behaviour of roofed open or closed structure: thus, under a specific purpose such as well-being of animals, light weight or low cost materials, the more suitable solution can be chosen. Simulated and experimental data fit well, although the software requires simple input values. Test performed on different types of roof materials show that composite roof, such as thin water-proof layer coupled with insulating material, has a better thermal behaviour respect to single-layer material. Moreover, insulating materials can be substituted by air space between two layers. Wooden layer was investigated as interior surface showing a good performance and an excellent pleasure at sight.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
