CFD modeling of the thermal environment in a negative pressure tunnel ventilated broiler barn during the first week of life

Abstract

For being located in warm weather and small temperature amplitude regions, Brazilian broiler producers usually opt for installations without thermal insulation on the sides, in order to enable the use of hybrid negative pressure tunnel ventilation. However, during early life stages, chicks should be protected from cold stress, especially in the winter. The question of whether the lack of lateral insulation compromises thermal comfort and adequate air speeds in the brooding area remains unanswered. It is known that depending on the intensity and duration, poor thermal environments in early life of broilers may cause irreversible damage on their performance. The objective of this research was to use Computational Fluid Dynamics (CFD) to evaluate the air velocity and temperature profiles in the brooding area of a broiler barn during the chicks’ first week of life. The non-insulated barn had double layers of polyethylene curtains on the sides, and was equipped with a negative pressure tunnel ventilation system. The validation of the full scale CFD model was performed with air velocity data collected in a real barn. The computer model showed no statistical difference compared to real conditions, in terms of air velocity. Based on the results, the need to expand the distance between double side curtains and roof-ceiling to increase insulation capacity was evident. Alternatively, decreasing the floor area allocated to the birds, keeping them away from areas of relatively high wind speeds can be a solution, allowing to an environment that ensures chicks´ adequate comfort and welfare.