CFD modeling of air quality inside naturally ventilated broiler barns as a function of barn spatial arrangement

One of the most effective ways to improve air quality inside high density poultry barns comes still during the conception of the farm project, such as adopting a minimum distance between naturally ventilated barns that will prevent, at least partially, the exhaust air from one barn to enter the next one downwind. The aim of this study was to use CFD (Computational Fluid Dynamics) to model ammonia (NH3) concentrations inside naturally ventilated broiler houses and to assess the influence of the surrounding of four poultry houses G1, G2, G3 and G4, all identical with the dimensions 13.5m W x 100m L x 3.5m H, under three typical house spatial arrangements. The different topologies were modeled: In arrangement A1, distances between barns will be as in A2 but the front wall of G2 will be translated 25 m to the axial direction as compared to the G1, and B3 25 m to the same axial direction as compared to G2.. For the second arrangement (A2), four poultry barns are positioned side by side with a distance of 35m (side-wall to side wall). For the one another arrangement (A3), the barn G2 will be located 35m from the G1 (downwind) but G3 will be positioned 100m downwind G2. Climatic conditions were being those of a typical summer day in a tropical region like Brazil. Ammonia concentration data was validated, and showed good agreement with experimental data, and the simulations indicated that the arrangement A1 reduced the cumulative effect of the upwind barns, presenting the best results.