Test of two different schemes through CFD to include heat and mass transfer induced by animals inside a broiler house

Abstract : Intensive production of broilers is seen as a promising way to efficiently operate livestock buildings. However, there are great concerns about the required optimal settings that accomplish the best living conditions for the animal. These living conditions strongly depend on the broiler house climate dynamics. The assessment of climate, incorporating the effects of the animals and equipment for climate control, can be done using Computational Fluid Dynamics (CFD). The CFD model developed in the course of this study includes the heat, water vapor and CO2 transfers between outdoors and indoors of the broiler house. But its primary distinction regards to the heat generated by the broiler and its solid manure since their emission rates modifies significantly the indoor climate dynamics due to the characteristic high animal density. This study splits the total heat produced by the animal, solid manure and heater between sensible and latent heat and also includes the CO2 produced within the broiler house. The animals are represented under two emitting heat schemes: 1) as an animal occupied zone and 2) as a porous medium. The benchmarking of these two schemes gets equivalent information about the density, weight, and size. Results of the simulations are compared with experiments conducted during a cycle of production. This comparison points out that the animal occupied zone scheme simplifies the incorporation of the heat and mass from the animals; alternatively, the porous zone scheme necessitates coefficients related to inertial and viscous forces either obtained by experiments or additional CFD simulations. Also, this work indicates the heat and mass contribution from animals and equipment used for heating that defines the environment conditions in a broiler house. The present study serves as the basis for an improved CFD model that could be used for predicting the climate dynamics in animal housing aiding to find the minimum energy required in the operation of equipment for climate control.