Computational Fluid Dynamics Modeling of Environmental Conditions in A Naturally Ventilated Free-Stall Dairy Barn

Abstract

An essential parameter for the design of a dairy barn is adequate ventilation. A well-ventilated barn benefits the environment and the animals by reducing stress and improving air quality. The aim of this research was to evaluate the spatial variability of environmental conditions in a free-stall dairy barn using computational fluid dynamics (CFD) modeling. Measurements of temperature and air velocity were made in the barn for comparison with the simulated results. The simulations were performed under steady-state conditions and considered the specific behavior of cows standing and lying down, as well as their distribution in the barn. The measured and predicted mean air temperatures in the barn were 21.50 ± 0.174 °C and 21.33 ± 0.213 °C, while the air velocities were 0.30 ± 0.196 m s-1 and 0.31 ± 0.197 m s-1, respectively. The results from CFD showed that the barn was not adequately ventilated, which could lead to severe problems for the cows inside. Consequently, the application of the proposed model CFD in simulating specific building design alternatives could aim to investigate the appropriate airflow distribution to find the best configuration.