Analysis of convective heat transfer in dairy cattle via computational fluid dynamics

This study aimed to evaluate convective heat transfer in dairy cattle during grazing in a tropical climate region through computational fluid dynamics (CFD) simulations. Furthermore, this study aimed to explore the relationship between an animal’s orientation and airflow during grazing. To achieve these objectives, a virtual bovine model was developed, incorporating detailed physiological and morphometric parameters, and subjected to CFD simulations employing the k-ɷ SST model. Local meteorological data from Chapadinha, Maranhão, Brazil, were employed to characterize the micrometeorological profile, and physiological parameters from four adult dairy cattle were measured to define simulation boundary conditions. The study revealed an average convective heat transfer of 88.85 W/m². Furthermore, the results demonstrated a notable variation in convective heat transfer, with a 33.5% increase when the orientation was altered from 0° to 30°, followed by a slight reduction of 2.29% when the orientation was increased to 45°. Hence, by employing CFD with the k-ω SST model, it was possible to estimate the convective heat loss of dairy cattle. The orientation of the animal relative to the airflow in the pasture significantly influences convective heat loss and should be considered in strategies and infrastructures designed to optimize heat transfer.