Hydraulic Engineering Commons^™

Nonlinear Breaking-Wave Characteristics In Lagrangian Coordinates, Wen-Jer Tseng, Chia-Yan Cheng

Journal of Marine Science and Technology–Taiwan

This paper presents a theoretical investigation of nonlinear surface-wave propagation over a sloping bottom. For a problem with nonlinear surface-wave propagation over a sloping bottom, a perturbation method is first used to find the analytical solution in order to derive the third order terms for the bottom slope  and the wave steepness  in the Eulerian system. Then, by transforming the flow field solution from the Eulerian system into the Lagrangian system, a more accurate wave profile is identified. By using the kinematic stability parameter, new theoretical breaking-wave characteristics are derived. The theoretical solutions are then compared with those …

Assessment Of Dynamic Response Of Offshore Jacket Platforms Subjects To Random Waves, Xiaoshuang Han, Weiliang Qiao, Bo Zhou

Journal of Marine Science and Technology–Taiwan

This paper presents a simplified approach to analyze the dynamic response of offshore jacket platform based on Timoshenko beam theory. In the study, the jacket platform is simulated as a non-uniform cantilever beam structure subjects to random waves. The assessment of dynamic performance is based on the power spectral densities, variances and spectral moments due to wave spectrum. A combination of Pseudo-excitation and Ritz method is proposed and adopted, such as the dynamic characteristics of the jacket platform can be solved more efficiently without a need to examine the modes of vibration. The proposed analytical method also provides a more …

Modeling Artificial Groundwater Recharge In The Santa Rosa Creek Watershed, Alexander J. Murray

Master's Theses

The Santa Rosa Creek Watershed is an approximately 48 mi2 large watershed located on the central coast of California. This watershed drains to the Pacific Ocean through Santa Rosa Creek as it passes through agricultural land and the town of Cambria. Historically the groundwater within the Santa Rosa Creek Watershed has been used for irrigation, municipal and domestic uses, and the creek is critical habitat steelhead trout. During dry years, there is less water for all uses. When low groundwater levels occur, water can be drawn out of the creek and into the soil, drying out steelhead habitat. Seven agricultural …

Modeling Of Distributary Channels Formed By A Large Sediment Diversion In Broken Marshland, Dylan Blaskey

LSU New Orleans Theses and Dissertations

A 2-D DELFT3D model was developed to address the morphological response of Barataria Bay, the sediment deposition rate in the receiving basin, and the impact on the existing distributary channels within the broken marsh system due to the proposed Mid-Barataria Sediment Diversion. The model had a mesh size sufficient to accurately represent the development of the distributary channels, localized flooding, erosion, and salinity in the basin. The model predicts that the receiving basin will experience extensive erosion during the first year the diversion is open creating three major distributary pathways which flood much of the basin in freshwater. Most locations …

2-D Non-Linear Finite Element Analysis Of Folsom Dam: Seismically Induced Separation And Pore Pressure Along The Soil-Concrete Interface, Grace Amoussou

Master of Science in Civil Engineering Theses

The seismic soil-concrete interface stability of composite dams has been an area of interest to many researchers. However, the true interface behavior during a seismic event has not been well understood. During a ground shaking, bonding and de-bonding action along the interface may cause significant separation of soil and concrete surfaces, and such a separation may take place at any depth along the interface creating a stability concern for the overall dam. Moreover, the repetitive nature of bonding/debonding behavior may induce excess pore pressure along the interface, which in turn, may trigger a liquefaction failure or a hydraulic fracture in …

Susceptibility Assessment Of Bank And Floodplain Erosion In Stream Restoration Using A Two-Dimensional Hydrodynamic., Fereshteh Noorbakhsh

Electronic Theses and Dissertations

In the design of stream restorations, boundary shear stress (shear stress) and velocity during high flow events are the key parameters in the assessment of the risk of morphological failure associated with channel bank and bed erosion and sediment transport. The use of two-dimensional hydrodynamic models (2D Models) is becoming more common to estimate critical shear stress and velocity for stream restoration projects. These models can give detailed distribution of shear stress and velocity over floodplain surfaces and channel. Obtaining reliable and correct estimates of stress and velocity require an accurate digital terrain model, estimates of input flows at the …

Melamine-Derived Graphene Foam As A Thermal Additive For Water Harvesting Applications, Emily Chase

Honors Theses

This project proposes the use of a novel melamine-derived graphene foam formed by high temperature pyrolysis under inert conditions for use as a thermal additive to absorbent crystals. The high thermal conductivity of graphene foam makes it an ideal candidate for use as a cheap, flexible, and light-weight alternative to previously used copper foam and metal organic frameworks. Following surface functionalization, graphene foam may be saturated with hydrophilic absorbent crystals. The primary objectives of this research are to optimize the synthesis process of such a graphene foam to obtain the highest purity product while maintaining foam flexibility and to study …

A Hybrid Experimental-Numerical Study On The Flow Topology In The Confluence Hydrodynamics Zone Of An Open Channel With Lateral Drainage Pipe Discharge, Mohammad Nazari-Sharabian

UNLV Theses, Dissertations, Professional Papers, and Capstones

To avoid disrupting the flow in flood control channels with lateral drainage pipes, or impact channel capacity, confluences are constructed at small angles (Maximum 30○). These small angles are costly to construct, since they require more real estate than greater angles.

By performing several laboratory experiments in the Fluid Dynamics Laboratory of the University of Nevada, Las Vegas (UNLV) and utilizing a numerical model (FLOW-3D), this study investigated the impact of submerged lateral drainage pipe discharges into rectangular open channels, on flow topology in the confluence hydrodynamics zone (CHZ). This was done across a range of channel widths, flow rates, …

An Evaluation Of Bank Storage At Lake Mead Reservoir In The Southwest United States, Jon Woodrow Wilson

UNLV Theses, Dissertations, Professional Papers, and Capstones

A water balance model is employed at Lake Mead to monitor and verify changing hydrology that affects total volume at the reservoir. Bank storage, which is defined as the volume of water captured in permeable lithologic layers subject to changes induced by contact and proximity to an open waterbody, is one component that is updated regularly and is based upon data and methods that were developed in the 1960’s from observations made within the first 30 years of the reservoir's maturation. Since this period, the reservoir has undergone further development and a current understanding of additional hydrologic affects to bank …

Sediment Outflow Under Simulated Rainfall Conditions With Varying Geotechnical Properties, Pranjay Joshi, Akhilesh Kumar, P. V. Singh, Jahangeer Jahangeer

Daugherty Water for Food Global Institute: Faculty Publications

The vulnerability of soil toward erosion might be reduced by having a good vegetative cover over the soil surface, slope improvement, and improving soil properties so that it is not easily detached and transported. However, the establishment of proper vegetative cover is a long process because it takes time for seeds to germinate and attain maturity. As an alternative approach, if soil resistance was increased by increasing the shear strength of soil against erosive forces offered by eroding agents, the soil system would become capable of withstanding the detachment of its particles on the application of shear stress. To achieve …

The Long-Term Outlook Of The Mississippi-Atchafalaya Bifurcation: A Convergence Of Engineering, Economics, And Deltaic Evolution, Thomas Mitchell Andrus

LSU Doctoral Dissertations

The most recent and currently active delta lobe of the Mississippi River (MR) is the Atchafalaya-Wax Lake lobe, which was initiated approximately 400 years ago as a result of MR stream capture by the Atchafalaya River (AR). This capture process accelerated in the early to mid-1900s but further progress was prevented by construction and operation of the Old River Control Structure (ORCS) Complex. Many recent studies indicate that MR system below the ORCS is on a retreating geologic trajectory due to contributing factors such as sea level rise, subsidence, faulting, and declining hydraulic stream power. Diversions along the Lower MR …

Using Fuzzy Models And Time Series Analysis To Predict Water Quality, Zhao Fu, Mei Yang, Jacimaria R. Batista

Electrical & Computer Engineering Faculty Research

Water quality prediction is very important for both water resource scheduling and management. Simple linear regression analysis and artificial neural network models cannot accurately forecast water quality because of complicated linear and nonlinear relationships in the water quality dataset. An adaptive neuro-fuzzy inference system (ANFIS) that can integrate linear and nonlinear relationships has been proposed to address the problem. However, the ANFIS model can only work in scenarios where input and target parameters have strong correlations. In this paper, a fuzzy model integrated with a time series data analysis method is proposed to address the water quality prediction problem when …

Water Scarcity And Fish Imperilment Driven By Beef Production, Brian D. Richter, Dominique Bartak, Peter Caldwell, Kyle Fankel Davis, Peter Debaere, Arjen Y. Hoekstra, Tianshu Li, Landon Marston, Ryan Mcmanamay, Mesfin Mekonnen, Benjamin L. Ruddell, Richard R. Rushforth, Tara J. Troy

Daugherty Water for Food Global Institute: Faculty Publications

Human consumption of freshwater is now approaching or surpassing the rate at which water sources are being naturally replenished in many regions, creating water shortage risks for people and ecosystems. Here we assess the impact of human water uses and their connection to water scarcity and ecological damage across the United States, identify primary causes of river dewatering and explore ways to ameliorate them. We find irrigation of cattle-feed crops to be the greatest consumer of river water in the western United States, implicating beef and dairy consumption as the leading driver of water shortages and fish imperilment in the …

Maize Growth, Yield, Water Productivity And Evapotranspiration Response To Different Irrigation Methods And Amounts And Different Timing And Methods Of Nitrogen Applications, Ali T. Mohammed

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

Declining the quantity and quality of freshwater resources in many parts of the world, including Midwestern USA, especially in the light of rapidly growing world’s population and changing climate, imposes significant and, in some cases imminent, challenges for producers, policy- and decision-makers to produce more yield with less water and other inputs, particularly in water scarcity regions.

There is not comprehensive previous research has quantified and evaluated coupled impacts of irrigation rates and nitrogen timing management strategies and their interactions on maize (Zea mays L.) productivity and its various attributed efficiency index metrics under different irrigation methods under the …

Assessment Of An Automated Calibration Of The Sebal Algorithm To Estimate Dry-Season Surface-Energy Partitioning In A Forest–Savanna Transition In Brazil, Leonardo Laipelt, Anderson Luis Ruhoff, Ayan Santos Fleischmann, Rafael Henrique Bloedow Kayser, Elisa De Mello Kich, Humberto Ribeiro Da Rocha, Christopher Michael Usher Neale

Daugherty Water for Food Global Institute: Faculty Publications

Evapotranspiration (ET) provides a strong connection between surface energy and hydrological cycles. Advancements in remote sensing techniques have increased our understanding of energy and terrestrial water balances as well as the interaction between surface and atmosphere over large areas. In this study, we computed surface energy fluxes using the Surface Energy Balance Algorithm for Land (SEBAL) algorithm and a simplified adaptation of the CIMEC (Calibration using Inverse Modeling at Extreme Conditions) process for automated endmember selection. Our main purpose was to assess and compare the accuracy of the automated calibration of the SEBAL algorithm using two different sources of meteorological …

Results Of Improvement Of The Technological Process Of Sorting Of Draged Seeds, R.K. Djamolov, E.T. Maksudov, K. Djamolov

Irrigation and Melioration

The article presents the results of experiments conducted to justify the parameters of the seed selection unit to improve the process of sorting seeds. The experiments were carried out by changing the angle of inclination of the seed tray to the horizontal plane from α = 390 to α = 540 and the radius of the lower part of the tray in the aisle R = 140-180 mm. The experimental results show that the bottom of the tray, made in the form of a semicircle, allows the seeds to move up the pipe when the seeds fall from the tray …

Model Development To Assess Groundwater Flooding And Levee Underseepage In New Orleans, Louisiana, Shuo Yang

LSU Master's Theses

Flooding is a major threat to New Orleans due to its geographic location and geologic condition. However, potential groundwater flooding is seldom studied and poorly understood even though groundwater level is expected high in the city. High groundwater level might result in groundwater flooding in low-lying areas. High uplift pore water pressures may cause strong underseepage and risk levee safety. The objective of this study is to assess the impacts of hydrogeology on groundwater flooding and evaluate potential underseepage-induced hazards along levees in New Orleans. In this study, a groundwater flow model development which involves stratigraphy modeling, groundwater flow model …

Effect Of Channelized And Unchannelized Lateral Outflow On Three-Dimensional Flow Structure And Sediment Transport Mechanisms In A River Delta, Mohammad Kifayath Chowdhury

LSU Master's Theses

Spatial and temporal patterns in three-dimensional flow structure have been linked to channel morphology and processes in many environments, including river meander bends, confluences-diffluences, and bedrock canyons. However, there is not yet an understanding of how channelized and gradual, distributed lateral outflows that are often prevalent in deltaic distributary systems influence three-dimensional flow structure and sediment transport mechanisms. This thesis presents an analysis of 3D flow structure data collected from Wax Lake Delta, a naturally developing river-dominated delta in the northern Gulf of Mexico. Three hydrographic surveys were conducted using boat-mounted acoustic Doppler current profiler (ADCP) at two sites: an …

Permanent Vibrodiagnosis Of The Pump Unit, F.A. Bekchanov

Irrigation and Melioration

Currently, increasing the efficiency of operation of pumping stations is associated with the development of energy-saving and resource-saving technologies. Diagnostics is one of the modern and perfect ways to determine the main malfunctions that occur in pumping units. The main goal of diagnosing the technical condition of pumping units is to preliminarily identify the occurring malfunctions in it and ensure durability, reliability, reliability and operational efficiency. The article presents the effect of vibration on pumping units and analysis of methods of vibration diagnostics, information is given on the possibility and advantages of devices for continuous vibration diagnostics.

Energy Saving Issues In Pumping Units, A.I. Anarbaev, D.B. Kodirov, R.A. Zakhidov, B. Usmanov

Irrigation and Melioration

The article presents the issues of energy saving, which are becoming increasingly relevant due to the constant increase in tariffs and the introduction of the demands on energy efficiency and energy conversation. To save energy at pumping units, the characteristics of controlling the electric drive of pumping stations with frequency-controlled control are considered. For adequate adjustment by the technological process of water movement and power supply, corresponding analytical dependencies are obtained. An analysis of the physical expressions of water pumping processes allowed us to determine energy-saving modes of operation and technologies for improving the efficiency of equipment.

Importance Of Creating A System Of Land And Cadastral Data For Subjects Of Agriculture, К. Rakhmonov, M.O. Abdurakhimova

Irrigation and Melioration

A separate model and model were developed for compiling cadastral maps used by the authors for agricultural organizations. The model is intended for enterprises operating in the Tashkent region. The article is based on the scientific and methodological order and the system of destruction of irrigated lands. Based on the experience of leading foreign countries in this area, the possibilities of introducing modern electronic computers in Uzbekistan are presented. The procedure for converting data into a specific algorithm is recommended for the formation of a system of land cadastral data in agricultural entities. It is necessary to create an information …

Apple Orchard Drip Irrigation Conditions Of The Tashkent Region Of Uzbekistan, Sardor Gulyamov, Bakir Serikbaev, Anvar Sherov

Irrigation and Melioration

The article presents the results of many years of theoretical experimental field research on drip irrigation of the apple orchard of the Golden variety in the conditions of the Tashkent region. Based on the analysis of climatic, soil, hydrogeological, geological, hydrological and economic conditions of the experimental plot, as well as biological features of the garden, the values of total water consumption, water consumption deficit, irrigation, irrigation rate and the number of irrigation by the bioclimatic method are determined.

Calculation Of The Placement Of Vertical Drainage Wells Near An Open Water Source In The Conditions Of Waterlogging Of Built-Up Areas, B.K. Saliev

Irrigation and Melioration

The article discusses the methodology for calculating the intercepting drainage well that reveals the upper layer of the multilayer horizon, and presents analytical dependencies based on the hydrodynamic theory and formulas for approximate calculation of the location of the axial line of the blocking drainage between the source of flooding and the protected built-up area from flooding. In particular, mathematical methods have been improved to solve the forecast problems of flooding in conditions of different pressure, based on the relationship between the depressions and the incoming flow of pressure water into the drainage well. The presence of underground pressure water …

Field Research Methods And Some Results For Distribution Of Suspended Sediment In Flow Constrained By Transverse Dams, M.R. Bakiev, K.T. Yakubov, O.M. Matkarimov, Z.B. Dovlatov

Irrigation and Melioration

The article presents methods for determining the main parameters of flow of medium hydraulic size sediment, turbidity, sampling methods in field and the instruments used for sampling, methods of processing the samples in laboratory. Methods for setting sections and gage points and conducting field and laboratory research have been developed for flow deformed by blank and through flow transverse dams, water surface longitudinal and transverse slope takes place in the flow constrained by transverse dams, changes in suspended sediment distribution occur inversely. Location of sections for sampling is determined in the article: in the headrace –beyond dam influence zone, maximal …

Hydromechanical Parameters Of River Sediment, A.M. Arifjanov, D.Sh. Allayorov

Irrigation and Melioration

The main problem today in irrigation canals is the danger of siltation, in this process it is important to correctly assess the factors affecting the throughput (hydromechanical parameters of sediment) and using their justification of the hydraulic elements of the flow. The article presents the results of theoretical studies of the main hydromechanical parameters (hydraulic fineness) of river sediments, in hydraulic structures, in particular in irrigation canals, which currently increasingly affect adversely moving water. It has been established that the hydraulic size entering the right bank irrigation sump of the Kokand hydropower complex varies in the range of 189-429 mm/s, …

Design Dimensions Of Flow In Compressed Flow Beyond Combined Dikes, O. Kodirov, О. Хаlimbetov

Irrigation and Melioration

The experimental research has shown that the kinematic pattern of flow deformed by combined structures (core part is blank and made of local materials, and the head part is made of piles), and it is more complicated than usual, although the qualitative flow schemes have much in common. The flow has the zones of backup, compression and spreading. Compression zone is discussed in the article, and the largest transverse and longitudinal drops in elevation and velocity are observed in this zone, therefore theoretically it is very difficult to set the main design dimensions of flow in this zone. Therefore, the …

Certain Particularities Of Hydrotechical Concrete Water Permeabity, F.R. Yunusova, T.D. Muslimov

Irrigation and Melioration

The article discusses the issues of hydrotechnical concrete water permeability based on the requirements set to them, methods for determining concrete water permeability, characteristics of porosity and capillaries formed in concrete, as well as possibilities to decrease hydrotechnical concrete water permeability with the use of chemical admixtures and colmatation.

Determination Of Water Discharge Of A Jet Device Taking Into Account Mutflow Flow, Q.T. Rakhimov, D.A. Abduraimova

Irrigation and Melioration

In many sectors of the water economy, one can observe the movement of a sediment stream in pressured systems. The pressure losses in the liquid and sediment joint stream are different than the movement of a single-phase flow according to their pressure loss. In this case, some difficulties arise in determining the coefficients that affect the flow rate and the average flow rate. In the article given theoretical and experimental foundations for determining the hydraulic flow parameters in during the movement of a sediment and liquid flow. Theoretical studies are based on the laws of energy conservation, and laboratory studies …

Minimizing Control Circuits Using Logic Elements, R.T. Gaziyeva, A.M. Nigmatov, E.O. Ozodov

Irrigation and Melioration

In this article considered information about contact and non-contact automation. In most cases, contact automation is used in many pumping stations. These phenomena are a power surge or voltage drop. And also the use of contact automation occupies a large place and inconvenience in operation. Non- contactless automation solves these problems. Pumping stations are usually designed with the calculation of their operation without permanent duty personnel. At large stations, a small staff is provided, which primarily carries out control functions. Set the automatic operation of pumping units. Often, automatic selection of switched-on units is carried out, reserve is withdrawn, station …

Importance Of Creating A System Of Land And Cadastral Data For Subjects Of Agriculture, К. Rakhmonov

Irrigation and Melioration

The generation of electronic data using the land plot scheme while maintaining the land cadastre provides significant convenience for users. Based on this concept, the author explains the conditions, factors and elements of the formation of the contours of land within the land, which plays an important role in the land cadastral work. In particular, the elements of the contour of the earth, that is, the conditions and composition of the border, the area and the order of formation of numbers, are reflected in a separate figure. It is known that the composition of agricultural land plays an important role …