Dispersion of Livestock Building Ventilation Using Windbreaks and Ducts

Abstract

Installations of windbreak walls, short ducts, and stacks on livestock and poultrybuildings are described. With each, some vertical deflection of airflow (elevation of discharge)improves dispersion. In the case of windbreak walls downwind of exhaust fans, increasedmixing of odorous plumes into wind flow near the ground is achieved. Gaussian dispersiontheory shows that, except for tall stacks (greater than 15 m in height) or very close neighbors(e.g. within 0.5 km), dilution and dispersion using these devices is not expected to eliminateodor nuisances. Air cleaning or treatment within structures designed to enhance dispersionmay provide adequate reductions.