Journal of Animal Environmental ScienceISSN:1226-0274(Print)(사)한국축산환경학회

The length of air flow measurement device for measuring the ventilation rate from a pig barn is an factor that affects the estimation of ventilation rate. This study focused on ventilation rate comparison according to the length of air flow measurement device of hood-type. The pig barns (5 m × 8 m × 7 m) was installed an mechanically forced exhaust fan of chimney-type. The ventilation rate respectively was evaluated on 1) the device of length by a long (5 parts duct) or short (3 parts duct) and 2) whether the device was installed or not to a exhaust fan. At this time, there were also conducted in the condition of the presence or absence of a honeycomb duct, which was the last phase of the device. Both experiments were tested according to the operating rate of the exhaust fan (30, 50, 70, and 100%). The ventilation rate were lower in the long-length device than in the short-length from both experiments. In experiment 2, the reduction rate of ventilation rate compared with non-installed was higher in the long-length device than in the short-length. In conclusion, the findings confirmed that long-length device was caused the underestimate of ventilation rate.