In animal housing the roof plays a primary role in the determination of the thermal exchanges of the animals. In particular, in a hot climate, a high thermal resistance in diurnal hours can be helpful in order to reduce the effect of the solar radiation. But by increasing the thermal resistance it is reduced the possibility of discharging heat through the roof in the nocturnal hours. To reduce the diurnal negative effect of the radiant heat load, the use of insulating materials is often recommended. But this is an expensive solution the usefulness of which is not ascertained, depending on various factors: climate, latitude, building geometry and orientation, constructive solutions, animal physical and spatial parameters. This study aimed at investigating the effective influence of the roof constructive parameters on the animal heat exchange during the whole day, trying to find out the optimal solutions for different combinations of the more relevant factors: insulation, slope, orientation, height, shape. The internal surface temperature of the roof has been calculated by means of a dynamic model that takes into account all aspects affecting the internal environment; in particular the view factor between the roof and a hypothetical animal has been calculated as a function of different influencing parameters: roof sloping, eaves height, roof type (gabled and multi shed roof). This study has been carried out both on simple shelters and closed buildings, considering dairy cows and pigs.
The Influence of the Roof Characteristics on the Thermal Exchange in Animal Housing
LIBERATI, PAOLO;ZAPPAVIGNA, PAOLO
2008
Abstract
In animal housing the roof plays a primary role in the determination of the thermal exchanges of the animals. In particular, in a hot climate, a high thermal resistance in diurnal hours can be helpful in order to reduce the effect of the solar radiation. But by increasing the thermal resistance it is reduced the possibility of discharging heat through the roof in the nocturnal hours. To reduce the diurnal negative effect of the radiant heat load, the use of insulating materials is often recommended. But this is an expensive solution the usefulness of which is not ascertained, depending on various factors: climate, latitude, building geometry and orientation, constructive solutions, animal physical and spatial parameters. This study aimed at investigating the effective influence of the roof constructive parameters on the animal heat exchange during the whole day, trying to find out the optimal solutions for different combinations of the more relevant factors: insulation, slope, orientation, height, shape. The internal surface temperature of the roof has been calculated by means of a dynamic model that takes into account all aspects affecting the internal environment; in particular the view factor between the roof and a hypothetical animal has been calculated as a function of different influencing parameters: roof sloping, eaves height, roof type (gabled and multi shed roof). This study has been carried out both on simple shelters and closed buildings, considering dairy cows and pigs.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
