Steady-state balance model to calculate the indoor climate of livestock buildings, demonstrated for finishing pigs

The indoor climate of livestock buildings is of importance for the well-bei ng and health of animals and their production performance (daily weight gai n, milk yield etc). By using a steady-state model for the sensible and late nt heat fluxes and the CO2 and odour mass flows, the indoor climate of mech anically ventilated livestock buildings can be calculated. These equations depend on the livestock (number of animals and how they are kept), the insu lation of the building and the characteristics of the ventilation system (v entilation rate). Since the model can only be applied to animal houses wher e the ventilation systems are mechanically controlled (this is the case for a majority of finishing pig units), the calculations were done for an exam ple of a finishing pig unit with 1000 animal places. The model presented us ed 30 min values of the outdoor parameters temperature and humidity, collec ted over 2-year period, as input. The projected environment inside the live stock building was compared with recommended values. The duration of conden sation on the inside surfaces was also calculated.