Application of manure on agricultural lands may release considerable amounts of air pollutants, including gases, particulate matter, and odors, potentially impacting workers, animals, and community health. The objectives of this research are to quantify and compare fugitive emissions (gases, dust, and odors) from five manure types (swine, beef and dairy cattle, and poultry with and without litter) when applied on the field using six spreading methods. Three application techniques were used for solid manure: two conventional spreaders (horizontal and vertical beaters), and a novel prototype for direct incorporation of manure. The three other options were used for liquid manure: splash plate, dribble bar, and dribble bar with immediate incorporation. Each manure and spreader combination was performed in 3 repetitions, from June to November 2023. Preliminary results of field spreading experiments for swine manure showed that incorporation reduced odors and tended to decrease the concentration of ammonia (NH3). Carbon dioxide (CO2) and methane (CH4) concentrations increased slightly when spreading with a splash plate. Odor intensity was substantially greater with the splash plate compared to the dribble bar with incorporation (approximately 2–6 times). Moreover, the splash plate dispersed more particles during application than other methods. Additional findings on other manure types are currently being analyzed and will be included in the final paper.

In Wisconsin, America’s Dairyland, optimizing liquid manure application is crucial for sustainable and profitable farming. Traditional application methods pose environmental challenges, including nutrient runoff and odour emission. This study presents an innovative liquid manure applicator design, underpinned by extensive use of numerical simulations, specifically Finite Element Analysis (FEA), Discrete Element Method (DEM), and Computational Fluid Dynamics (CFD). These simulations played a pivotal role in every phase of the design process – from initial concept to final validation. They allowed for precise modelling of the structural integrity of applicator and soil and fluid dynamics, facilitating the development of three distinct and effective designs: a sweep injector, a disk injector, and a vertical tillage incorporation toolbar. Numerical simulations were integral in predicting the performance under various design alternations and operational conditions, ensuring resilience against mechanical stresses, and optimizing the environmental footprint. This comprehensive simulation-led approach was instrumental in developing the applicator that stands at the intersection of agricultural efficiency and environmental sustainability. By bridging advanced engineering techniques with practical agricultural needs, the project underscores the transformative potential of numerical simulations in modern agricultural/biosystems engineering.

Slurry and manure from animals are valuable sources of plant nutrients, including nitrogen, phosphorus, and potassium. However, over-fertilization poses a significant environmental challenge, leading to the volatilization of excess nitrogen and contributing to various issues such as air pollution, eutrophication, acidification, and greenhouse gas release. Effectively addressing ammonia emissions during manure spreading is crucial for mitigating these environmental problems. The mitigation of ammonia emissions not only brings environmental benefits but also holds social advantages by reducing the adverse effects of ammonia emissions on human health. Recognizing the growing interest in low-cost measurement methods due to their accessibility, affordability, portability, and user-friendly nature, this research aims to bridge a critical knowledge gap regarding the accuracy of these methods, particularly at low concentrations. To address this gap, the study compares ammonia emissions during manure spreading under controlled conditions, employing two low-cost methods: 1) a novel prototype of a passive flux sampler and 2) a dynamic chamber coupled with an acid trap. The experiment, conducted in four controlled rooms, involved the application of pig slurry to a layer of loamy clay soil (120 x 180 x 12 cm), with and without incorporation. The results not only validate the performance of the new low-cost ammonia sampler under controlled conditions but also enable a comprehensive comparison of the accuracy of each method. This research contributes valuable insights towards developing effective and affordable strategies for managing ammonia emissions during agricultural practices.

Understanding corn stalk cutting behaviors under the impact of disc is critical for designing disc for conservation tillage. In this study, three discs (notched, rippled, and plain disc) were examined on the effects of travel speed on corn stalk cutting behaviors using a stalk-disc-soil interaction model developed by the discrete element method. Soil was modelled using spherical particles. Corn stalk was modelled by bonded spherical particles, forming a solid and breakable model of corn stalk. During the simulation, model corn stalks were placed on soil surface and cut as the disc advanced. Dynamic attributes, including stalk cutting forces, stalk displacements, and soil sinkage under the pressure of stalks were monitored. Comparing the simulation values of stalking cutting force with experiment results in literature, the calibrated model parameters of corn stalk were 2 × 10^9 N m^-1 for bond stiffness, 8 × 10^6 Pa for bond strength, and 0.5 for particle friction. The anticipated results are that the model has a low relative error as comparing with measured in a soil bin test. Among three discs, the rippled disc has the least stalk cutting force, following by the notched disc and plain disc. Increasing the travel speed of discs increases stalk displacements, while reduces stalk cutting forces and soil sinkage. The results demonstrated that the stalk-disc-soil is feasible to obtain dynamic attributes of the interaction between soil, disc, and corn stalks during the process of tillage.

Air jet pumps allow the transportation of agricultural materials with no moving parts in the air stream. They function by using a jet of air to entrain and draw air through the duct, which draws in product and conveys it to its intended destination. This research examined the influence of duct shape on air entrainment in air jet pumps used for agricultural material conveyance. By employing computational fluid dynamics (CFD) modelling alongside experimental validation, various duct shapes were analyzed to determine their impact on air entrainment efficiency. The air jet pump was optimized by maximizing air entrainment for a given mass flow.

Common seed manifold designs involve complex interactions between seeds, air, and machine boundaries that are better understood through computer simulations. One-way coupling of Computational Fluid Dynamics (CFD) and Discrete Element Method (DEM) was applied to model seed dynamic attributes (trajectory, velocity, and force) in an air seeder manifold. Simulated field peas (Pisum sativum) were pneumatically conveyed at a rate of 0.07 kg/s, three air velocities (20, 25, and 30 m/s) and three manifold inclination angles (θ = 0°, 11°, and 22°). Model validation was conducted through experiments with a test bench replicating the simulated conditions. Simulated seed trajectories were evenly distributed within the vertical tube and were not significantly affected by manifold inclination angle or inlet air velocity. Median seed contact force ranged between 0.44 N and 3.52 N and was affected by location within the simulated manifold areas (elbow, vertical tube, and manifold head). Contact force data showed that inlet air velocity was a significant factor in simulated seed contact force, while manifold inclination angle did not have an effect. Model validation results revealed that one-way CFD-DEM coupling can replicate experimental observations related to overall seed distribution patterns (R2=0.90). Increasing inlet air velocity promoted more uniform seed distributions, while increasing the manifold inclination angle had the opposite effect. The proposed method lacked accuracy in determining the actual number of seeds per outlet (RMSE = 120 seeds). However, it is complementary to experimental data. This method could be appropriate in benchmarking multiple seed manifold arrangements relative to a baseline design.