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Retention Of Swine Slurry Constituents In Soil And Crop Residue As Affected By Setback Distance, John E. Gilley, Shannon L. Bartelt-Hunt, Kent M. Eskridge, Xu Li, Amy M. Schmidt, Daniel D. Snow

Biological Systems Engineering: Papers and Publications

Setbacks are prescribed distances from surface waters within which manure application is not allowed. Little information is available concerning the retention of swine slurry constituents in soil and crop residue materials within setback areas. This study was conducted to measure the retention of selected constituents within a setback area following the upslope application of swine slurry and the introduction of simulated rainfall. The no-till cropland site had a slope gradient of 4.9% and a mean winter wheat residue cover of 7.73 Mg ha−1 . Soil and vegetative samples were collected on 3.7 m wide by 23.2 m long plots with …

Quantification Of Heat Flows Through Building Entrance Doors On A Winter Day, Daeho Kang

Publications and Research

The current methods for the prediction of the heat flow through building entrance doors have been used for years while involved with a certain degree of uncertainty. This paper describes an experimental method that accurately quantified such heat flow. The experiment monitored local environmental parameters in a college building on a cold winter day. The results of the experiment demonstrated that the experimental method is viable to accurately estimate the heat flow throughout the entrance doors and the presence of a vestibule moderated heat losses from the conditioned area. The results will be used for validating the existing methods.

An Urban Flash Flood Alert Tool For Megacities—Application For Manhattan, New York City, Usa, Rafea Hashim Al-Suhili, Cheila Cullen, Reza Khanbilvardi

Publications and Research

Urban flooding is a frequent problem affecting cities all over the world. The problem is more significant now that the climate is changing and urbanization trends are increasing. Various, physical hydrological models such as the Environmental Protection Agency Storm Water Management Model (EPA SWMM), MIKE URBAN-II and others, have been developed to simulate flooding events in cities. However, they require high accuracy mapping and a simulation of the underground storm drainage system. Sadly, this capability is usually not available for older or larger so-called megacities. Other hydrological model types are classified in the semi-physical category, like Cellular Automata (CA), require …

A Novel Approach To Visualize And Quantify The Transient Air Infiltration/Exfiltration In Walk-In Coolers, Ramin Faramarzi, Homayun K. Navaz, K. Kamensky

Mechanical Engineering Publications

Walk-in coolers are room-sized, insulated, and refrigerated compartments for food product storage. Walk-ins have areas equal or below 280 m2 (3,000 ft2), and are classified either as coolers operating above 0 degrees C (32 degrees F) (medium-temperature) to store fresh fruit, vegetables, and dairy products, or freezers that operate below 0 degrees C (32 degrees F) (low-temperature) to meet health and safety standards of frozen food products. Walk-ins are typically found in restaurants as well as small- and medium-to-large grocery stores or supermarkets.

Effects Of Vegetation On Slope Stability: A Review, Roberto José Marín Sánchez, Juan Pablo Osorio

Articles

Slope stability is usually affected by factors that reduce soil strength and increase driving forces acting on the slope material, sometimes generating mass movements. Among these factors, vegetation has an important role related to hydrological (e.g. evapotranspiration and infiltration) and mechanical (e.g. tree surcharge and root reinforcement provided by trees) mechanisms. In this review, vegetation influences associated to slope stability are identified, describing the mechanisms involved in the occurrence of mass movements. Finally, the way these factors affect slope stability is explained according to soil properties, climatic conditions and environmental characteristics.

Beyond The Scs-Cn Method: A Theoretical Framework For Spatially Lumped Rainfall-Runoff Response, Mark Bartlett, Anthony J. Parolari, Jeffrey Mcdonnell, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Since its introduction in 1954, the Soil Conservation Service curve number (SCS-CN) method has become the standard tool, in practice, for estimating an event-based rainfall-runoff response. However, because of its empirical origins, the SCS-CN method is restricted to certain geographic regions and land use types. Moreover, it does not describe the spatial variability of runoff. To move beyond these limitations, we present a new theoretical framework for spatially lumped, event-based rainfall-runoff modeling. In this framework, we describe the spatially lumped runoff model as a point description of runoff that is upscaled to a watershed area based on probability distributions that …

Heterogeneity Of Infiltration Rates In Alluvial Floodplains As Measured With A Berm Infiltration Technique, Derek M. Heeren, Garey A. Fox, Daniel E. Storm

Biological Systems Engineering: Papers and Publications

Hydrologic heterogeneities (e.g., macropores and gravel outcrops) in floodplains are hypothesized to play an integral role in impacting flow and leaching between the soil surface and shallow alluvial aquifers, which are intricately connected to streams. Infiltration is often assumed to be uniform, but this neglects the spatial variability common in anisotropic, heterogeneous alluvial floodplain soils. The objective of this research was to quantify infiltration and hydraulic conductivity across a range of scales (point to 100 m²) using a berm infiltration technique. Plot-scale leaching experiments were performed across a range of soil types at each of three floodplain sites …

Single- And Dual-Porosity Calibration And Long-Term Modeling Of Highly Conductive Floodplain Soils In The Ozark Ecoregion, Ryan P. Freiberger

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Phosphorus (P) is a critical nutrient for agriculture, but is also responsible for surface water enrichment that leads to algal growth. While P loading to surface waters has traditionally been thought to occur from surface runoff, contributions from subsurface transport can also be significant. Subsurface transport through gravelly soils in the Ozark ecoregion can have a significant, yet poorly-documented effect on P movement to groundwater.

Long-term P modeling was performed in HYDRUS-1D and 2D using data collected from short-term plot experiments featuring gravelly soils. Seven model levels were developed to illustrate a wide variety of laboratory and field conditions. Calibration …

Finite Element Modeling Of Long-Term Phosphorus Leaching Through Macropores In The Ozark Ecoregion, Ryan P. Freiberger, Derek M. Heeren, Garey A. Fox, Chad J. Penn, Dean E. Eisenhauer

Biological Systems Engineering: Papers and Publications

Phosphorus (P) is a critical nutrient for plant growth in agriculture, but is also responsible for surface water enrichment that leads to toxic algal growth. While P loading to surface waters has traditionally been thought to occur from surface runoff, contributions from subsurface transport can also be significant. While P transport through many soil types is well-documented, the presence of highly conductive gravel outcrops and macropore networks can have a significant, yet poorly-documented effect on P movement to the aquifer. Floodplain soils in the Ozark ecoregion generally contain coarse chert gravel layers that exhibit macropore behavior. Previous research has evaluated …

Berm Method For Quantification Of Infiltration At The Plot Scale In High Conductivity Soils, Derek M. Heeren, Garey A. Fox, Daniel E. Storm

Biological Systems Engineering: Papers and Publications

Measuring infiltration at the plot scale is difficult, especially for high hydraulic conductivity soils. At the plot scale, the infiltration rate is usually calculated by comparing surface runoff to rainfall. Direct measurement of infiltration beyond the point scale is typically limited to locations where land forming (e.g., infiltration pond) has been performed or fields with basin irrigation systems. The standard method for field measurement of point-scale infiltration is the double ring infiltrometer, which is limited in size (typically 30 cm diameter). In this research, a new method is proposed that uses a temporary berm constructed of a water-filled 15-cm diameter …

Finite Element Modeling Of Phosphorus Leaching Through Floodplain Soils Dominated By Preferential Flow Pathways, Ryan P. Freiberger, Derek M. Heeren, Garey A. Fox

Biological Systems Engineering: Papers and Publications

Phosphorus is a critical nutrient in soils, providing both positive and negative effects to different systems. While optimum crop growth requires a range of P above 0.2 mg/L, preventing surface water enrichment generally requires P to be below 0.03 mg/L. Proper application and control of phosphorus is important to increase farming efficiency and to protect freshwater systems from toxic algal growth. While the movement of phosphorus through many soil types has been well-documented, the presence of highly conductive, gravel outcrops and macropores in soil can have a significant, poorly-documented effect on phosphorus movement. In the Ozark ecoregion, for example, the …

Impact Of Measurement Scale On Infiltration And Phosphorus Leaching In Ozark Floodplains, Derek M. Heeren, Garey A. Fox, Daniel E. Storm, Brian E. Haggard, Chad J. Penn, Todd Halihan

Biological Systems Engineering: Papers and Publications

Increased nutrient loads have resulted in several adverse impacts on surface water quality, including excessive algal growth, fish kills, and drinking water taste and odor issues across the United States and especially in the Ozark ecoregion of northeastern Oklahoma and northwestern Arkansas. The significance of this problem has been highlighted by litigation, with one case even reaching the U.S. Supreme Court (Arkansas et al. v. Oklahoma et al., 503 U.S. 91) which required the upstream state to meet downstream water quality standards. The overarching objective of this line of research was to characterize phosphorus leaching to alluvial aquifers in the …

Designing Contour Weep Berms To Reduce Agricultural Nonpoint Source Pollution, Richard C. Warner, Carmen T. Agouridis, Ross L. Guffey

Biosystems and Agricultural Engineering Faculty Publications

Nonpoint source pollution (NPS) of surface waters is a significant issue in agricultural lands, and best management practices (BMPs) are often used to reduce these impacts. Since the effectiveness of a BMP depends on a large number of widely varying factors, it is important to continue to develop BMPs in order to provide designers with more tools to use to maximize NPS removal. The contour weep berm is a new structural BMP constructed out of earth and subsequently vegetated. It is a linear BMP that is used in combination with a down-gradient vegetated filter strip or forested riparian buffer. Preliminary …

Reconfigurable Photonic Crystal Waveguides Created By Selectrive Liquid Infiltration, A Casas Bedoya, P Domachuk, C Grillet, C Monat, E Magi, Enbang Li, Benjamin J. Eggleton

Faculty of Engineering and Information Sciences - Papers: Part A

We experimentally demonstrate reconfigurable photonic crystal waveguides created directly by infiltrating high refractive index (n≈2.01) liquids into selected air holes of a two-dimensional hexagonal periodic lattice in silicon. The resulting effective index contrast is large enough that a single row of infiltrated holes enables light propagation at near-infrared wavelengths. We include a detailed comparison between modeling and experimental results of single line defect waveguides and show how our infiltration procedure is reversible and repeatable. We achieve infiltration accuracy down to the single air hole level and demonstrate control on the volume of liquid infused into the holes by simply changing …

Berm Method For Quantification Of Infiltration And Leaching At The Plot Scale In High Conductivity Soils, Derek M. Heeren, Garey A. Fox, Daniel E. Storm

Biological Systems Engineering: Papers and Publications

Measuring infiltration and leaching at the plot scale is difficult, especially for high hydraulic conductivity soils. Infiltration rate has been indirectly calculated at the plot scale by comparing surface runoff to rainfall. Direct measurement of infiltration and leaching beyond the point scale is typically limited to locations where land forming has been performed, e.g. infiltration ponds and fields with basin irrigation. The standard method for field measurement of infiltration is a double ring infiltrometer, which is limited in size (typically 30 cm diameter). In this research, a new method is proposed that uses a temporary berm constructed of a water …

Simulation Of Water Movement Through Unsaturated Infiltration-Redistribution System, Thidarat Bunsri, Muttucumaru Sivakumar, Dharmappa Hagare

Faculty of Engineering - Papers (Archive)

This paper deals with the movement of water in a natural unsaturated zone, focusing on infiltration-redistribution system. Infiltration refers to the downward movement of water due to the gravitational force and redistribution defines the upward movement of water due to the capillary rise. Under natural conditions, the movement of water through an infiltration-redistribution depended upon the relations among water content, hydraulic conductivity and tension of soil pore. Various combinations of water balance concepts, Richards' equation, soil-physics theory and capillary height concepts were applied to mathematically model the movement of water through infiltration-redistribution system. The accuracy and computational efficiency of the …

A Physically Based Two-Dimensional Infiltration Model For Furrow Irrigation, Christopher J. Skonard, Derrel L. Martin

Department of Biological Systems Engineering: Conference Presentations and White Papers

A two-dimensional physically based infiltration model was developed for furrow
irrigation. Infiltration was simulated using the Green-Ampt infiltration method. The Green-Ampt infiltration parameters are available from numerous sources, unlike the Kostiakov infiltration parameters. Simulation tests showed the two-dimensional model capable of estimating cumulative infiltration volume within 8% compared to simulated infiltration using the finite element model, Hydrus-2D. Application of the two-dimensional model in a surface irrigation advance model allows irrigation performance parameters to be predicted without extensive soil experiments.

Seepage Characteristics And Hydraulic Properties Of A Feedlot Runoff Storage Pond, David B. Parker, Dean E. Eisenhauer, Dennis D. Schulte, John A. Nienaber

Biological Systems Engineering: Papers and Publications

Water and chemical transport were investigated beneath a 22-year-old beef feedlot runoff storage pond. Soil and sludge samples were collected from 14 borings to 6.1-m depths in a cross-section across the pond. The soils consisted of silt loam and clay loam, and the groundwater level was about 30 m beneath the land surface. Soil samples were analyzed for pH, NO₃-N, NH₄-N, Cl, P, K, SO₄-S, TKN, and organic matter. Physical and hydraulic properties were measured on undisturbed samples of soil and sludge to compare saturated hydraulic conductivity, moisture release characteristics, and bulk density. Saturated …

Validating A Vegetative Filter Strip Performance Model, Puneet Srivastava, Thomas A. Costello, Dwayne R. Edwards, James A. Ferguson

Biosystems and Agricultural Engineering Faculty Publications

Vegetative filter strips (VFS) reduce losses of nutrients, solids, and other materials from land area treated with fertilizers and manures. A number of models are available that simulate nutrient and sediment transport in VFS. While VFS effectiveness is considered to depend on lengths of pollutant source area and VFS areas, few published studies have tried to validate these models using variable pollutant source area and VFS area. The objective of this study was to validate an event-based nutrient transport model (Chaubey et al., 1995) that simulates soluble nutrient transport in VFS. This model links three sub-models: modified Green-Ampt infiltration, non-linear …

A Direct, Approximate Solution To The Modified Green-Ampt Infiltration Equation, Puneet Srivastava, Thomas A. Costello, Dwayne R. Edwards

Biosystems and Agricultural Engineering Faculty Publications

Accurately predicting the rainfall-runoff process is of vital importance for water quality models as well as for correct design of various types of hydraulic structures. This article presents a method of describing the cumulative infiltration process as an explicit function of time using an approximation to the modified Green-Ampt equation given by Mein and Larson (1971). The resulting equation is helpful in predicting cumulative infiltration and therefore infiltration capacity for computer simulation models. The proposed method takes about 50% less time than the usual iterative technique for the same degree of accuracy. The maximum error due to approximation was 1% …

Infiltration Through Reconstructed Surface Mined Spoils And Soils, A. D. Ward, Larry G. Wells, R. E. Phillips

Biosystems and Agricultural Engineering Faculty Publications

An extensive series of tests involving reconstructed profiles of spoil and topsoil material from a Western Kentucky surface mine site was conducted with a laboratory infiltrometer system. Infiltration through the reconstructed spoil profiles was very slow despite the coarse nature of the material. Low infiltration rates could be attributed to the material having a well-graded texture and to the high densities of the profiles. Infiltration through topsoil horizons was controlled, for the most part, by conditions at the surface. Following wetting, infiltration rates were primarily controlled by the hydraulic characteristics of the less permeable sub horizon of the spoil material. …