Analysis of Poultry House Ventilation Using Computational Fluid Dynamics

Abstract

The airflow in and around poultry houses was studied numerically with the goal of determining the disease spread characteristics and comparing two ventilation schemes. A typical manure-belt laying hen egg production facility was considered. The continuity, momentum, and energy equations were solved for flow both inside and outside poultry houses using the commercial computational fluid dynamics (CFD) code FLUENT. The geometry was constructed by making some simplifying assumptions, such as two-dimensionality. The spread of virus particles was considered analogous to diffusion of a tracer contaminant gas, in this case ammonia (NH3). The effect of thermal plumes produced by the hens in the poultry house was also taken into consideration. Two ventilation schemes with opposite flow directions were compared. Contours of temperature and contaminant mass fraction for both cases were obtained and compared. The analysis shows that ventilation and air quality characteristics were much better for the case in which the airflow was from bottom to top instead of from top to bottom (top to bottom is how most current poultry houses are configured). This has implications for air quality control in the event of epidemic outbreaks. Decreased contaminant spread to downwind poultry houses was observed in the bottom-to-top airflow scheme.