University of Tehran Press Iranian Journal of Biosystem Engineering 2008-4803 49 4 2019 02 20 Calculating the Ventilation Rate of Broiler Chick Salon by Carbon Dioxide Balance Method and Comparison with Direct Measurement Method Calculating the Ventilation Rate of Broiler Chick Salon by Carbon Dioxide Balance Method and Comparison with Direct Measurement Method 659 668 70019 10.22059/ijbse.2018.249787.665029 FA Mousareza Baghani Department of Biosystems Mechanical Engineering, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran Mohammad Hossein Aghkhani Professor in Department of Mechanical Engineering Biosystem. Faculty of Agriculture. Ferdowsi University Of Mashhad. Iran. Journal Article 2018 01 15 Ventilation rate of the poultries can be calculated by directly and indirectly method. This research was carried out in poultry with population of 18,000 broiler chicks in Sabzavar to compare these two methods. The output air velocity was measured in each of the fans at 24 points of the fan surface to measure the ventilation rate directly. The average speed at the effective surface of the fans was also calculated. The ventilation rate in the CO₂ equilibrium method was obtained by calculating the CO₂ production rate of chicks and measuring the CO₂ concentration at the air inlets and outlets of the poultry, using the equations of gas balance in control volume. The results showed that the difference in two methods of measurement in different conditions of the salon was less than 22% (12500 m³/h) and with increasing ventilation rate, the difference between the two methods decreased to 2%. Ventilation rate of the poultries can be calculated by directly and indirectly method. This research was carried out in poultry with population of 18,000 broiler chicks in Sabzavar to compare these two methods. The output air velocity was measured in each of the fans at 24 points of the fan surface to measure the ventilation rate directly. The average speed at the effective surface of the fans was also calculated. The ventilation rate in the CO₂ equilibrium method was obtained by calculating the CO₂ production rate of chicks and measuring the CO₂ concentration at the air inlets and outlets of the poultry, using the equations of gas balance in control volume. The results showed that the difference in two methods of measurement in different conditions of the salon was less than 22% (12500 m³/h) and with increasing ventilation rate, the difference between the two methods decreased to 2%. https://ijbse.ut.ac.ir/article_70019_ed9487970298632234c8cac97d8d4cf5.pdf