CFD model for ventilation assessment in poultry houses with different distribution of windows

Abstract

The design of structures for animal husbandry has energy and environmental implications. Particularly, the design of broiler houses should consider the comfort of animals in different situations, which is crucial for their proper development. Building geometry and distribution of fans and windows determine critically the ventilation flows and temperature distribution. The use of fluid analysis techniques can be of valuable help in the initial phases of the design of farms, because potential alternatives may be explored. In this study, Computational Fluid Dynamics (CFD) simulations were used to evaluate the ventilation and temperature distribution in three tunnel, mechanically ventilated broiler houses with identical geometry but different distribution of inlet windows and exhaust fans. The three distributions were: (1) Tunnel (fans at the end of the building); (2) Semitunnel (fans at the middle of the building); and (3) Improved Semitunnel (with improved window distribution). For each distribution, air velocity and temperature at the height of the broilers are evaluated at different outdoor conditions. The Index of Temperature and Velocity (ITV) was used as an indicator of animal comfort. Improved tunnel presented more homogeneous values of velocity and air temperature, with average velocity of 0.89 ± 0.30m.s-1 and average temperature of 23.37 ± 0.79ºC. This distribution had the highest comfort area considering air velocity and temperature (88.45% and 94.52% of the area, respectively). The lowest average ITV corresponded to tunnel type (23.24 ± 1.54ºC) but the highest proportion of comfort zone considering ITV (ITV<25) corresponded to the improved semitunnel (90.35% of the area). The three configurations maintained a productive environment of ITV. The simulation results were similar to the literature indications for velocities and temperatures at animal level.