APPLICATION OF A COMPUTER-MODEL FOR NATURALLY VENTILATED LIVESTOCK BUILDINGS IN ALBERTA UNDER SUMMER CONDITIONS

NatVent, a computer model for predicting the performance of natural ve ntilation in livestock buildings and greenhouses, was evaluated using data collected in summer from two naturally-ventilated swine barns. An insulated, naturally-ventilated weaner-grower barn was monitored in L acombe, and a new naturally-ventilated finisher pig barn was monitored in Olds, both in Alberta. The barn at Lacombe met the open country cr iteria required by NatVent and the measured results and NatVent predic tions were in good agreement (R-2 = 0.98). Because the barn at Olds wa s attached to another structure, its measured ventilation rates were l ower than those predicted by NatVent when the wind was from the direct ion of the attached structure.