This review article on the topic of livestock odor dispersion modeling focuses on odor sources, odor emission rates, odor characteristics and measurements, odor dispersion modeling methods, and methods and results of adapting industrial air dispersion models for livestock odor dispersion simulations. The Gaussian plume models, puff models, fluctuating plume models, and other models that have been applied in livestock odor dispersion modeling are explicitly reviewed. Research work on validation or evaluation of industrial air dispersion models using various field odor plume measurement results, scaling factor or peak-to-mean ratio, and various relationships between odor concentration and odor intensity generated by different studies is also discussed. Although many Gaussian models have been applied in livestock odor dispersion and have achieved relatively satisfactory results, there are many differences between traditional industrial air pollutants and livestock odor, including emission sources, travel distances, and most importantly, measurement methods and the inherent instantaneous characteristic of livestock odor that can challenge the use of Gaussian models. The research on applying advanced air dispersion models such as fluctuating plume models, Lagrangian stochastic models, and computational fluid dynamics (CFD) models in odor dispersion modeling is very limited. As a result, it is found necessary to develop an improved model that can accurately predict livestock odor concentration downwind of the sources. More specifically; a fluctuating plume model that has the ability to consider short time fluctuations of odor concentration is suggested for livestock odor dispersion within the short distances that are typically of interest in odor dispersion modeling.
