Abstract
The inside air temperature, the floor surface temperature and the amount of ventilation air of two windowless poultry houses in summer were measured, and the heat flow through the floor was analyzed theoretically.
1. The average overall heat transmission coefficients of two houses were 0.23 and 0.81kcal/m2•°C•hr, respectively. According to these values, the houses were estimated to be thermally well insulated.
2. It was theoretically proved that the floor temperature was under periodic steady-state. The periodic change of floor heat flow was, then, calculated as shown in Table 2.
3. The amount of heat flowed into the houses mentiond aboved and a house having 2kcal/m2•°C•hr of heat transmission coefficient were calculated from the values of the sol-air temperature in August and the inside temperature of houses.
Then, the ratios of the outflow of heat through the floor to the inflow into the houses were obtained, being 5.82, 2.49 and 0.76 times, respectively, by the order of insulation. The ratios of the floor heat loss to the total loss through floor and by ventilation air were also calculated, being 49.2, 51.8 and 31.4%, respectively.
In conclusion, in summer the heat flow from the inside of the house into the ground through the floor may play a very important role in the thermal environment of the well insulated windowless poultry houses for layers.
