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Gokgoz, Kilic Sinem. "Dynamic fugacity modeling in environmental systems." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22557.
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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2008.<br>Committee Chair: Aral, Mustafa; Committee Member: Guan, Jiabao; Committee Member: Pavlostathis, Spyros; Committee Member: Uzer, Turgay; Committee Member: Yiacoumi, Sotira.
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Hesterlee, Craig D. "Dynamic modeling of West Point Reservoir hydrothermal and algal growth forcing mechanisms." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/20732.
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Yang, Xueyao. "Real-time Probabilistic Contaminant Source Identification and Model-Based Event Detection Algorithms." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1385114685.
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Smith, Edwin L. "A system dynamics computer model for long-term water quality planning." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/41562.
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<p>The objective of this study was to develop a comprehensive,
basin-wide, water-quality-planning model using system dynamics
methodology. Later, the model was to be interfaced with
a more conventional system dynamics model: one simulating
social, technological, economic, and political interactions.
By doing so, it is envisioned that such management policies
as zoning, abatement facilities, and best management practices
may be simulated together.</p><br>Master of Science
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Mohammadighavam, S. (Shahram). "Hydrological and hydraulic design of peatland drainage and water treatment systems for optimal control of diffuse pollution." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526214511.
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Abstract Peatland drainage for forestry, agriculture and peat extraction results in runoff rich in organic matter, sediments and nutrients. This has a significant effect on downstream ecosystems. Therefore, water purification using sedimentation basins and wetlands is required in environmental permits for peat extraction in Finland, to reduce downstream impacts. Due to increasingly strict environmental regulations, more advanced water purification methods need to be developed. Using field measurements, laboratory experiments and hydrological/hydraulic modelling, this thesis sought to develop new methods based on: i) more refined hydrological information related to runoff and pollutant load control and ii) hydraulic design of sedimentation basins used in chemical purification. The hydrology of three peatland forestry and two drained peat extraction areas in northern Finland was studied and simulated using the DRAINMOD 6.1 hydrological model. Watertable depth (WTD) and drainage outflow were recorded continuously during several years and the data were used for model calibration and validation. Despite some under- and over-estimation of certain events, WTD fluctuations were simulated quite accurately for all peatland areas. The results demonstrated that DRAINMOD 6.1 can satisfactorily simulate WTD fluctuations in a cold climate such as northern Finland, but the model did not simulate drainage outflow adequately. Chemical treatment facilities were optimised using 3D computational fluid dynamic (CFD) models. COMSOL Multiphysics 5.1 was employed to evaluate the influence of inlet design on treatment efficiency in commonly used treatment basins without any barrier, and for optimization of barrier design through gravity-driven hydraulic flocculators. The results showed that inlet design had a significant effect on treatment efficiency. Several barrier designs were simulated and the best combination was tested for different distances between barriers, to find a geometry ratio and flow depth producing optimal mixing conditions for the treatment process<br>Tiivistelmä Turvemaiden ojitus metsätaloutta, maataloutta ja turvetuotantoa varten lisää orgaanisen aineen, kiintoaineineen ja ravinteiden huuhtoutumista alapuolisiin vesistöihin. Lisääntyneellä kuormituksella voi olla merkittäviä vaikutuksia vesiekosysteemeihin, minkä vuoksi turvetuotannon ympäristöluvissa vaaditaan valumavesien puhdistamista mm. laskeutusaltaiden ja pintavalutuskenttien avulla. Tiukentuneiden vesiensuojelumääräysten vuoksi tarvitaan uusia vesiensuojelumenetelmiä sekä tulee tehostaa jo käytössä olevien menetelmien toimintaa. Tämän työn tavoitteena on suositella uusia menetelmiä perustuen I) entistä tarkempaan hydrologiseen tietoon valunnasta ja vesistökuormituksesta ja II) kemiallisen vesienpuhdistuksen yhteydessä käytettävien laskeutusaltaiden hydrauliseen suunnitteluun. Tämä väitöstyö rakentuu maastossa ja laboratoriossa tehtyjen tutkimusten sekä hydrologisen/hydraulisen mallinnuksen varaan. Valuma-alueiden hydrologiaa tutkittiin ja mallinnettiin kolmella turvemetsäalueella ja kahdella turvetuotantoalueella Pohjois-Suomessa. Ojituksen hydrologisten vaikutusten arviointiin käytettiin DRAINMOD 6.1 ohjelmaa, jonka kalibrointia ja validointia varten kerättiin jatkuvatoimisilla antureilla aineistoa pohjaveden pinnankorkeuksista ja virtaamasta useiden vuosien ajalta. Mallin avulla voitiin pohjaveden pinnan vaihtelut kuvata yleisesti melko hyvin kaikilla tutkimusalueilla yksittäisistä sadanta-valuntatapahtuminen yli- tai aliarvioinneista huolimatta. Saadut tulokset osoittavat, että DRAINMOD 6.1 ohjelmalla voidaan riittävällä tarkkuudella simuloida pohjaveden pinnan vaihteluita kylmässä ilmastossa, kuten Pohjois-Suomessa, mutta malli ei soveltunut hyvin ojitusalueelta lähtevän valunnan tarkkaan määrittämiseen. Kemiallisen vesienpuhdistusrakenteiden optimointiin käytettiin COMSOL Multiphysics 5.1 ohjelmaa, jolla voidaan toteuttaa ja laskea veden virtauksia kolmessa dimensiossa (computational fluid dynamic, CFD, model). Mallilla arvioitiin kemikalointialtaan tuloaukon rakenteen vaikutuksia tyypillisesti kemikaloinnissa käytetyn allasrakenteen puhdistustehokkuuteen. Lisäksi mallilla mitoitettiin virtausesteitä optimaalisen sekoittumisolosuhteiden saamiseksi ja puhdistustehokkuuden parantamiseksi painovoimaisesti toimivissa flokkausaltaissa (hidas sekoitus). Saadut tulokset osoittavat, että laskeutusaltaiden tuloaukon rakenteella on merkittävä vaikutus kemikaloinnissa saavutettuun puhdistustehokkuuteen. Lisäksi työssä esitettiin optimaalisia virtausesteiden mitoituksia (geometria, esteiden välinen etäisyys, virtaussyvyys yms.) puhdistuksen kannalta parhaiden mahdollisten sekoitusolosuhteiden saavuttamiseksi
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Finley, Allan Michael. "Application of system dynamics modeling techniques to an existing stream water quality model." Master's thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-02162010-020040/.
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Castro, Antonio Paulo. "Dynamic water quality modeling using cellular automata." Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-06062008-151210/.
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Sincock, Andrew Michael. "Conceptual river water quality modelling under dynamic conditions." Thesis, Imperial College London, 2002. http://hdl.handle.net/10044/1/11912.
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Kim, Sei Jin. "Three Essays on the Implications of Environmental Policy on Nutrient Outputs in Agricultural Watersheds and the Heterogeneous Global Timber Model with Uncertainty Analysis." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1439601683.
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Pasha, Md Fayzul Kabir. "Uncertainty Analysis and Calibration of Water Distribution Quality Models." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/194289.
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Water distribution system modeling can be used as a basis of planning and operation decisions. However, model accuracy and uncertainty will impact the model based decisions. Model prediction uncertainty results from uncertainty in model parameters that are determined through calibration or are based upon modeler judgment. The focus of this dissertation is the effect of uncertainties on water quality model estimates and calibration. The dissertation is centered around three journal articles and a technical note.In the first paper, the effect of parameter uncertainty on water quality in a distribution system under steady and unsteady conditions was analyzed by Monte Carlo simulation (MCS). Sources of uncertainties for water quality include decay coefficients, pipe diameter and roughness, and nodal spatial and temporal demands. The effect of individual parameter is discussed, as well as the combined effect of the parameters. It also describes the effect of flow patterns.A general calibration model is developed in the second paper for identifying wall decay coefficients. The problem is solved using the SFLA optimization algorithm that is coupled with hydraulic and water quality simulation models using the EPANET toolkit. The methodology is applied on two application networks. The study presents the effect of different field conditions such as the network with or without tanks, altering disinfectant injection policies, changing measurement locations, and varying the number of global wall decay coefficient on the estimated parameters. The numerical study also discusses whether the complexity of the system can be captured with fewer than the actual number of field parameters and if the number of the measurement locations is sufficient.The third paper conducts a study that considers a full calibration assessment for a water quality model in the distribution systems. The calibration process begins with estimating the the best fit wall decay coefficients. Next, the uncertainties involved with estimated parameters are calculated. Finally, the study assesses the model prediction uncertainties for critical demand conditions due to the parameter uncertainties. Various conditions are evaluated including the effects of different measurement errors and different measurement conditions on the uncertainty levels of estimated parameters as well as on the model predictions.Fourth paper presents study in which a booster disinfectant is introduced within a distribution system to maintain disinfectant residuals and avoid high dosages at water sources. Assuming that first order reaction kinetics apply to chlorine decay, an integer linear programming optimization problem is posed to booster locations and their injection rates. The formulation avoids long water quality simulations by adding constraints requiring the concentrations at the beginning and end of the design period to be the same. The optimization problem is divided into two levels. The upper level selects the booster locations using a genetic algorithm, if more than a few boosters are included, or enumeration, if the number of boosters and/or potential locations is relatively small. Given a set of boosters from the upper level, the lower level minimizes the chlorine mass to be injected to maintain required residuals. The approach is applied to the Brushy Plains system for alternative numbers of allowable boosters.
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El, Didy Sherif Mohamed Ahmed 1951. "Two-dimensional finite element programs for water flow and water quality in multi-aquifer systems." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/191110.
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Multiple aquifer systems similar to those that exist at coal gasification sites are complicated groundwater situations. In these types of systems, the aquifers are separated by aquitards through which interaction between aquifers can occur. The movement of the products of combustion into the coal seam and adjacent aquifers is a serious problem of interest. This dissertation presents two-dimensional finite element models for water flow and water quality in multiple aquifer systems. These models can be applied for general problems as well as the problems associated with the burned cavities in coal gasification sites. The Galerkin weightedresidual method is used in both models. Eight-noded isoparametric elements are used. Spatial numerical integration is performed using Gaussian quadrature. A weighted finite difference scheme is used, in both of them, for time integration. The two models are written in FORTRAN V for the CDC CYBER 175. They are applicable to one- or two-dimensional problems involving steady-state or transient flow. Each aquifer can have different initial conditions and boundary conditions. Boundary conditions, pumping rates, and the recharge can be specified as a function of time. The output of the flow program-nodal heads and velocity components is used as an input to the quality program. The numerical models were validated for simple problems that have available analytical solutions.
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Tillman, Dorothy Hamlin. "Coupling of ecological and water quality models for improved water resource and fish management." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2334.
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Li, Yan. "An integrated water quality monitoring system with dynamic remote sensing feedback /." Online version of thesis, 2007. http://hdl.handle.net/1850/5834.
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Berger, Christopher John. "Water Quality Modeling of the Tualitin River." PDXScholar, 1993. https://pdxscholar.library.pdx.edu/open_access_etds/4742.
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Water quality problems related to excessive algal growth, high nutrient loading, and low flows have been occurring along Oregon's Tualatin River. The Tualatin River is 86 miles long and has a drainage basin of 711 square miles. The drainage basin incorporates forest, agricultural, and urban areas. Located in the Portland metropolitan area, these problems have been acerbated by the effects of urban growth. To help analyze pollution control alternatives, a river model study, funded by the Oregon Department of Environmental Quality (DEQ}, was undertaken. An in-stream model of hydraulics and water quality was developed. The Corps of Engineer's CE-QUAL-W2 model, a twodimensional, laterally averaged, dynamic model of hydrodynamics and water quality was applied to the Tualatin system. Calibration of the main pool model of the Tualatin River was from field data taken during June through August of 1991. Verification of the model was performed from field data taken during the summer of 1990. After calibration and verification of the model, management alternatives were evaluated in order to achieve DEQ mandated water quality standards. Environmental performance criteria were determined to evaluate differences between model scenarios. Management alternatives focused on the reduction of point and non-point sources of pollution, flow augmentation, and structural changes in the river system, such as removal of the Lake Oswego Diversion Dam.
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Tang, Ling 1963. "Interfacing hydrodynamic and water quality models with the Eulerian-Lagrangian method." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9637.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1998.<br>Includes bibliographical references.<br>The problem of interfacing hydrodynamic and water quality models is investigated with emphasis on modeling efficiency, accuracy and flexibility. An Eulerian-Lagrangian type of transport model is proposed for interfacing due to its superior simulation efficiency and numerical resolution in advection dominant flows. Comparisons are made between Eulerian models and Eulerian-Lagrangian models through both theoretical analyses and numerical studies of mass conservation and concentration accuracy. A mass conservative model, such as an Eulerian type model, will not necessarily guarantee concentration accuracy. As part of this research, a three dimensional EulerianLagrangian transport model (ELM3D) is developed and validated. The interfacing efficiency of ELM3D is demonstrated through a series of numerical tracer studies simulating the future outfall in Massachusetts Bay. Comparison against a traditional Eulerian model, ECOMsi, shows that an Eulerian-Lagrangian interfacing with a proper mass correction technique, such as total mass scaling, can serve as an efficient transport tool, which is more robust than conventional Eulerian Models in dealing with advection dominant flows.<br>by Ling Tang.<br>Ph.D.
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Cox, Brian A. "Dynamic modelling of dissolved oxygen : a case-study for the River Thames." Thesis, University of Reading, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250691.
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Gorrie, Jason Robert. "An Examination Of Water Quality Impacts On Lake Manassas." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/32815.
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Lake Manassas is a man-made impoundment in the Northern Virginia suburbs of Washington, D.C. The lake currently supplies drinking water at an average rate of 10.5 million gallons per day to the City of Manassas, Virginia. The lake discharges, via the Broad Run, a tributary of the Occoquan Reservoir. The Occoquan Reservoir supplies potable water to over 750,000 people in the Northern Virginia area.
This thesis presents the results of a limnological analysis of Lake Manassas. The techniques used are established limnological techniques to arrive at a profile which can be compared to accepted scales of ranking.
One conclusion from the analysis is that Lake Manassas is eutrophic, which means that the production of biomass in the lake is at a higher than desired rate. The result of this eutrophic condition is that the water quality of the lake will decline rather rapidly. Another conclusion is that Broad Run is the major supplier of nutrients into Lake Manassas, but that conditions are also affected by a point source discharge from a sewage treatment plant. These conclusions are consistent with previous studies done on Lake Manassas.
In summary, Lake Manassas is an important water resource in the Northern Virginia area, and it is important to continue to closely monitor and manage runoff practices in the watershed to ensure the lake does not degrade to unacceptable conditions.<br>Master of Science
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Shojaei, Nasim. "Automatic Calibration of Water Quality and Hydrodynamic Model (CE-QUAL-W2)." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1942.
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One of the most important purposes of surface water resource management is to develop predictive models to assist in identifying and evaluating operational and structural measures for improving water quality. To better understand the effects of external and internal nutrient and organic loading and the effects of reservoir operation, a model is often developed, calibrated, and used for sensitivity and management simulations. The importance of modeling and simulation in the scientific community has drawn interest towards methods for automated calibration. This study addresses using an automatic technique to calibrate the water quality model CE-QUAL-W2 (Cole and Wells, 2013). CE-QUAL-W2 is a two-dimensional (2D) longitudinal/vertical hydrodynamic and water quality model for surface water bodies, modeling eutrophication processes such as temperature-nutrient-algae-dissolved oxygen-organic matter and sediment relationships. The numerical method used for calibration in this study is the particle swarm optimization method developed by Kennedy and Eberhart (1995) and inspired by the paradigm of birds flocking. The objective of this calibration procedure is to choose model parameters and coefficients affecting temperature, chlorophyll a, dissolved oxygen, and nutrients (such as NH4, NO3, and PO4). A case study is presented for the Karkheh Reservoir in Iran with a capacity of more than 5 billion cubic meters that is the largest dam in Iran with both agricultural and drinking water usages. This algorithm is shown to perform very well for determining model parameters for the reservoir water quality and hydrodynamic model. Implications of the use of this procedure for other water quality models are also shown.
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Hashim, Noor Baharim. "Watershed, hydrodynamic, and water quality models for total maximum daily load St. Louis Bay watershed Mississippi." Diss., Mississippi State : Mississippi State University, 2001. http://library.msstate.edu/etd/show.asp?etd=etd-04102001-154624.
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Smith, Kimberly C. (Kimberly Carolyn). "Evaluating PC-based water quality models as tools for land use planning." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/70200.
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Heller, Winfried. "Hydro-dynamic Effects with Particular Consideration of Water Quality and their Measurement Methods." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1141217614058-76453.
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Die Entwicklung der Strömungsmechanik im 20. Jahrhundert wurde auch durch intensive Forschungen geprägt, um die zahlreichen in der Praxis auftretenden hydrodynamischen Effekte zu ergründen, die physikalischen Abläufe und Zusammenhänge zu verstehen und diese mathematisch zu beschreiben. Dies wurde notwendig, da mit den hydrodynamischen Grundgleichungen allein keine Beschreibung der aus den Fluideigenschaften resultierenden Erscheinungen in Flüssigkeitsströmungen möglich war. Um die Qualität der Flüssigkeiten bezüglich ihres Gasgehaltes und ihrer Keimverteilung beurteilen zu können, wurden mit Beginn des 20. Jahrhunderts unterschiedliche Messmethoden und Apparaturen entwickelt und gebaut. Diese Entwicklung ließ sich annähernd vollständig darstellen, hierbei besonders die Entwicklungen von Apparaturen zur Bestimmung des Gesamtgasgehaltes. Neben der zumeist schwierigen Handhabung dieser Messgeräte und Methoden wird dabei nur der Einfluss einzelner Messgrößen, wie Gesamtgasgehalt, Gelöstsauerstoffgehalt, Keimgehalt, Keimverteilung und Keimgrößenverteilung auf hydrodynamische Effekte untersucht. Die aber in realen Strömungen auftretenden Wechselwirkungen zwischen den Einflussgrößen werden nicht berücksichtigt. Schon am Ende des 19. Jahrhundert begann die Entwicklung von Geräten und Methoden zur Bestimmung von Zugspannungen in Flüssigkeiten. Den anfänglich statischen Methoden folgten mit Beginn der 70-er Jahre des 20. Jahrhunderts die bis heute andauernden Entwicklungen dynamischer Methoden. Während für speziell behandelte Flüssigkeiten unter statischen Bedingungen Zugspannungen von einigen hundert bar gemessen wurden, liegen die typischen Werte für Wasser mit der Wirbel- oder Dralldüse gemessen, zwischen null und zwei bar. Das zeigt den starken Einfluss der Wechselwirkungen aller Einflussgrößen auf die Zugspannung in strömenden Flüssigkeiten. Außer auf die Schallgeschwindigkeit und die Druckverteilung an Profilen hat die Wasserqualität einen besonders starken Einfluss auf bestimmte Kavitationserscheinungen. Weltweite Kavitationstests zeigten, dass ohne Bestimmung der aktuellen Zugspannung des Testwassers keine reproduzierbaren Ergebnisse bezüglich des Kavitationsbeginns möglich sind. Bei Untersuchungen zur Kavitationserosion wurde der Zusammenhang zwischen Wasserqualität und erosiver Aggressivität und Erosionsrate eindeutig nachgewiesen. Die permanente Messung der Zugspannung der Testflüssigkeit ist bei Kavitationsexperimenten an Modellkörpern offensichtlich zwingend notwendig, um die Messergebnisse korrekt interpretieren zu können. Kavitationserscheinungen an Profilen oder Durchströmteilen bewirken Änderungen von Auftriebs-, Widerstands- und Verlustbeiwerten in Abhängigkeit vom Fortschrittsgrad der Kavitation. Hierbei spielen die Beeinflussung der Transition, Ablösung, Versperrung und Druckverteilung eine besondere Rolle. Bei elektrisch leitfähigen Fluiden ist die Qualität durch die Leitfähigkeit bestimmt. Mittels elektromagnetischer Felder werden Lorentzkräfte erzeugt, deren Wirkung sich zeigt in der Unterdrückung von Strömungsablösung, Widerstandsverringerung und stärkerem Auftrieb. Vielfältige experimentelle Forschungsergebnisse auf dem Gebiet der Strömungsmechanik haben gezeigt, dass für die Beschreibung realer Strömungsvorgänge die Qualität des Fluides berücksichtigt werden muss. Da die vielen Einflussgrößen in der Strömung permanenten Wechselwirkungen unterliegen, führt letztlich die Summe aller Einzeleinflüsse auf die genannten Effekte. Für die Bestimmung der Wasserqualität z.B. bei Kavitationsexperimenten kann die Zugspannung des Testwassers gemessen werden, wodurch die genauere mathematische Beschreibung des Kavitationsbeginns möglich wird<br>The development of fluid mechanics during the twentieth century has been affected by intense research in order to fathom numerous practically relevant hydrodynamic effects, to understand the physical processes and correlations and to describe them mathematically. This became necessary because employing only the fundamental hydrodynamic equations, the description of certain phenomena in fluid flows caused by fluid properties was impossible. In order to assess the quality of fluids regarding their gas contents and their nuclei distributions, various measuring methods and devices have been developed and constructed since the beginning of the twentieth century. This historical development could be described nearly completely in this work, particularly the development of devices to determine the total gas content. Apart from the mostly difficult handling of these measurement methods and devices, only the influence of single parameters such as the total gas content, the dissolved oxygen content, nucleus content, nucleus distribution and the distribution of nucleus sizes on hydrodynamic effects was examined. However, the correlations between these single parameters, as they occur in real flows, could not be taken into consideration. As early as the end of the ninetieth century the development of methods and devices began to determine the tensile strength of fluids. The initially static methods have been followed by the developments of dynamic methods since the beginning of the 1970s. While for specially prepared fluids, tensile strengths of several hundred bar were measured under static conditions, the typical values for water, measured with the eddy and swirl nozzle, range between zero and two bar. This illustrates the strong influence of interactions between all parameters on the tensile strength in flowing fluids. Except for sound velocity and pressure distribution at profiles, water quality particularly affects certain cavitation phenomena. Various cavitation tests around the world have shown that without determining the actual tensile strength of the test water, it is impossible to obtain reproducible results regarding cavitation inception. In experiments concerning cavitation erosion, the correlation between water quality, erosive aggressiveness and erosion rate was proven unmistakably. Evidently, permanent measurement of the test fluid?s tensile stress during cavitation experiments with model bodies is compulsory in order to be able to interpret measurement results correctly. Cavitation phenomena at profiles or other parts affected by flow cause changes of lift, drag and loss coefficients depending on the degree of the cavitation progress. The influence of transition, detachment, obstruction and pressure distribution plays a special role. The quality of electrically conductive fluids is determined by their conductivity. By means of electromagnetic fields Lorentz-forces are generated, whose effect can be observed in lessening of flow detachment, drag reduction and increased lift. Manifold experimental research results in the area of fluid mechanics have proven that the fluid quality must be taken into account when describing real flow processes. Since the many flow parameters are subject to permanent interaction, ultimately, the sum of all single parameters lead to the effects mentioned. For the determination of the water quality such as in cavitation experiments, the tensile stress of the water can be measured making the mathematical description of cavitation inception possible. - (The German online version of this thesis for qualification as university teacher has been published under the titel &quot;Hydrodynamische Effekte unter besonderer Berücksichtigung der Wasserqualität und ihre Messverfahren&quot; - http://hsss.slub-dresden.de/hsss/servlet/hsss.urlmapping.MappingServlet?id=1141215758714-7391)
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Heller, Winfried. "Hydro-dynamic effects with particular consideration of water quality and their measurement methods." Doctoral thesis, Tönning; Lübeck; Marburg : Der Andere Verl, 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=979397405.
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Chen, Zhuo. "Dynamic compensation and sensor fusion for a GSM-based water quality monitoring network." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58372.
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With the increasing demand for water, access to clean water is becoming a more challenging problem for people, in both rural and urban communities. The quantity and quality of fresh water resources, both surface water and ground water, are of major concern worldwide. A continuous water quality monitoring system with access to accurate real-time data can play an important role in water quality tracking and environmental protection. However, evaluation of water quality is complicated; on the one hand, a great number of physical, chemical and biological parameters are usually involved. Hence, multi-sensors network is often deployed for collecting a variety of useful water quality information, such as pH value, ammonia concentration, oxidation-reduction potential, temperature, electrical conductivity, turbidity, and the concentration of dissolved oxygen. On the other hand, objectives of in situ testing are complex and dynamic, and the testing environment in the field is also dynamic and harsh. This thesis develops a wireless data transmission platform to solve the communication problem between the monitoring sensor nodes in the field and the base station. What’s more, an individual sensor is only able to make a judgment using a single parameter as evidence. Simplex information is neither sufficient nor reliable, and some parameters also have mutual interference with each other to some extent. Specifically, there should be a systematic way to integrate information from multiple sensors to obtain more accurate and reliable water quality information. Furthermore, allowance has to be made for the variation in the conditions of a sensor, which will affect the sensor accuracy. Therefore, compensation and fusion of sensory data from disparate sources are very necessary to secure a reliable, accurate, and comprehensive monitoring result. By applying Dempster-Shafer theory and Euclidean Distance, this thesis presents a method of assigning four different parameters in the same scale, and combining them into an integrated and reliable quality evaluation result. The necessary methodologies are systematically presented. They are applied to realistic sensory data to illustrate their application and effectiveness.<br>Applied Science, Faculty of<br>Mechanical Engineering, Department of<br>Graduate
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Viswanathan, Vinodh Kumar. "Dynamic model for small-capacity ammonia-water absorption chiller." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/48939.
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Optimization of the performance of absorption systems during transient operations such as start-up and shut-down is particularly important for small-capacity chillers and heat pumps to minimize lifecycle costs. Dynamic models in the literature have been used to study responses to step changes in a single parameter, but more complex processes such as system start-up have not been studied in detail. A robust system-level model for simulating the transient behavior of an absorption chiller is developed here.
Individual heat and mass exchangers are modeled using detailed segmental models. The UA-values and thermal masses of heat exchangers used in the model are representative of a practical operational chiller. Thermal masses of the heat exchangers and energy storage in the heat exchanging fluids are accounted for to achieve realistic transient simulation of the heat transfer processes in the chiller. The pressure drop due to fluid flow across the heat exchangers is considered negligible in comparison to the pressure difference between the high- and low-side components (~ 1.5 MPa). In components with significant mass transfer effects, reduced-order models are employed to decrease computational costs while also maintaining accurate system response.
Mass and species storage in the cycle are modeled using storage devices. The storage devices account for expansion and contraction of the refrigerant and solution in the cycle as the system goes through start-up, shut-down, and other transient events. A counterflow falling film desorber model is employed to account for the heat and mass transfer interactions between the liquid and vapor phases, inside the desorber. The liquid film flows down counter to the rising vapor, thereby exchanging heat with the counterflowing heated coupling fluid. A segmented model is used to account for these processes, and a solver is developed for performing rapid iteration and quick estimation of unknown vapor and liquid states at the outlet of each segment of the desorber. Other components such as the rectifier, expansion valves and solution pump are modeled as quasi-steady devices.
System start-up is simulated from ambient conditions, and the coupling fluid temperatures are assumed to start up to their steady-state values within the first 90 s of simulation. It is observed that the system attains steady-state in approximately 550 s. The evaporator cooling duty and COP of the chiller during steady-state are observed to be 3.41 kW and 0.60, respectively. Steady-state parameters such as flow rates, heat transfer rates and concentrations are found to match closely with results from simulations using corresponding steady-state models. Several control responses are investigated using this dynamic simulation model. System responses to step changes in the desorber coupling fluid temperature and flow rate, solution pumping rate, and valve setting are used to study the effects of several control strategies on system behavior. Results from this analysis can be used to optimize start-up and steady state performances. The model can also be used for devising and testing control strategies in commercial applications.
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Thoe, Wai. "Integrated river management of the East River field studies, hydrologic and water quality modelling /." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38997575.
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Glatthorn, Stephen. "VERIFICATION OF PILOT-SCALE IRON RELEASE MODELS." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4003.
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A model for the prediction of color release from a pilot distribution system was created in 2003 by Imran. This model allows prediction of the release of color from aged cast iron and galvanized steel pipes as a function of water quality and hydraulic residence time. Color was used as a surrogate measurement for iron, which exhibited a strong linear correlation. An anomaly of this model was an absence of a term to account for pH, due to the influent water being well stabilized. A new study was completed to evaluate the effectiveness of corrosion inhibitors against traditional adjustment. Two control lines were supplied with nearly same water qualities, one at pH close to pHs and one at pH well above pHs. The resulting data showed that effluent iron values were typically greater in the line with lower pH. The non-linear color model by Imran shows good agreement when the LSI was largely positive, but underpredicted the color release from the lower LSI line. A modification to the Larson Ratio proposed by Imran was able to give a reasonable agreement to the data at lower LSI values. LSI showed no definite relation to iron release, although a visual trend of higher LSI mitigating iron release can be seen. An iron flux model was also developed on the same pilot system by Mutoti. This model was based on a steady state mass balance of iron in a pipe. The constants for the model were empirically derived from experiments at different hydraulic conditions with a constant water quality. Experiments were assumed to reach steady state at 3 pipe volumes due to the near constant effluent turbidity achieved at this point. The model proposes that the iron flux under laminar flow conditions is constant, while the iron flux is linearly related to the Reynolds Number under turbulent conditions. This model incorporates the color release models developed by Imran to calculate flux values from different water qualities. A limited number of experiments were performed in the current study using desalinated and ground water sources at Reynolds Numbers ranging from 50 to 200. The results of these limited experiments showed that the iron flux for cast iron pipe was approximately one-half of the predicted values from Mutoti. This discrepancy may be caused by the more extensive flushing of the pipes performed on the current experiments which allowed attainment of a true steady state. Model changes were proposed to distinguish between near stagnant flow and the upper laminar region, with the upper laminar region showing a slight linear increase. Predictions using the galvanized flux model were not accurate due to an inferior color release model that was developed for galvanized pipes. The model exhibits a high dependence on sulfate concentrations, but concentrations of sulfates in the current experiments were low. This led to low predicted flux values when the actual data showed otherwise. A new galvanized model was developed from a combination of data from the original and current experiments. The predicted flux values using the new model showed great improvement over the old model, but the new model database was limited and the resulting model was not able to be independently tested.<br>M.S.<br>Department of Civil and Environmental Engineering<br>Engineering and Computer Science<br>Environmental Engr MSEnvE
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Hernandez, Murcia Oscar Eduardo. "Development of a highly resolved 3-D computational model for applications in water quality and ecosystems." Thesis, The University of Iowa, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3638380.
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<p> This dissertation presents the development and application of a computational model called BioChemFOAM developed using the computation fluid dynamic software OpenFOAM (Open source Field Operation And Manipulation). BioChemFOAM is a three dimensional incompressible unsteady-flow model that is coupled with a water-quality model via the Reynolds Average Navier-Stokes (RANS) equations. BioChemFOAM was developed to model nutrient dynamics in inland riverine aquatic ecosystems. BioChemFOAM solves the RANS equations for the hydrodynamics with an available library in OpenFOAM and implements a new library to include coupled systems of species transport equations with reactions. Simulation of the flow and multicomponent reactive transport are studied in detail for fundamental numerical experiments as well as for a real application in a backwater area of the Mississippi River. BioChemFOAM is a robust model that enables the flexible parameterization of processes for the nitrogen cycle. The processes studied include the following main components: algae, organic carbon, phosphorus, nitrogen, and dissolved oxygen. In particular, the research presented has three phases. The first phase involves the identification of the common processes that influence the nitrogen removal. The second phase covers the development and validation of the model that uses common parameterization to simulate the main features of an aquatic ecosystem. The main processes considered in the model and implemented in BioChemFOAM are: fully resolved hydraulic parameters (velocity and pressure), temperature variation, light's influence on the ecosystem, nutrients dynamics, algae growth and death, advection and diffusion of species, and isotropic turbulence (using a two-equation k-epsilon model). The final phase covers the application and analysis of the model and is divided in two sub stages: 1) a qualitative comparison of the main processes involved in the model (validation with the exact solution of different components of the model under different degrees of complexity) and 2) the quantification of main processes affecting nitrate removal in a backwater floodplain lake (Round Lake) in Pool 8 of the Mississippi River near La Crosse, WI. </p><p> The BioChemFOAM model was able to reproduce different levels of complexity in an aquatic ecosystem and expose several main features that may help understand nutrient dynamics. The validation process with fabricated numerical experiments, discussed in Chapter 4, not only presents a detailed evaluation of the equations and processes but also introduces a step-by-step method of validating the model, given a level of complexity and parameterization when modeling nutrient dynamics in aquatic ecosystems. The study cases maintain fixed coefficients and characteristic values of the concentration in order to compare the influences that increasing or decreasing complexity has on the model, BioChemFOAM. Chapter 4, which focuses on model validation with numerical experiments, demonstrates that, with characteristic concentration and coefficients, some processes do not greatly influence the nutrient dynamics for algae. </p><p> Chapters 5 and 6 discuss how BioChemFOAM was subsequently applied to an actual field case in the Mississippi River to show the model's ability to reproduce real world conditions when nitrate samples are available and other concentrations are used from typical monitored values. The model was able to reproduce the main processes affecting nutrient dynamics in the proposed scenarios and for previous studies in the literature. First, the model was adapted to simulate one species, nitrate, and its concentration was comparable to measured data. Second, the model was tested under different initial conditions. The model shows independence on initial conditions when reaching a steady mass flow rate for nitrate. Finally, a sensitivity analysis was performed using all eleven species in the model. The sensitivity takes as its basis the influence of processes on nitrate fate and transport and it defines eight scenarios. It was found in the present parameterization that green algae as modeled does not have a significant influence on improving nitrate spatial distributions and percentage of nitrate removal (PNR). On the other hand, reaction rates for denitrification at the bed and nitrification in the water shows an important influence on the nitrate spatial distribution and the PNR. One physical solution, from the broad range of scenarios defined in the sensitivity analysis, was selected as most closely reproducing the backwater natural system. The selection was based on published values of the percentage of nitrate removal (PNR), nitrate spatial concentrations, total nitrogen spatial concentrations and mass loading rate balances. The scenario identified as a physically valid solution has a reaction rate of nitrification and denitrification at the bed of 2.37x10<sup>-5</sup> s<sup>-1</sup>. The PNR was found to be 39% when reaching a steady solution for the species transport. The denitrification at the bed process was about 6.7% of the input nitrate mass loading rate and the nitrification was about 7.7% of the input nitrate mass loading rate. </p><p> The present research and model development highlight the need for additional detailed field measurements to reduce the uncertainty of common processes included in advanced models (see Chapter 2 for a review of models and Chapter 3 for the proposed model). The application presented in Chapter 6 utilizes only spatial variations of nitrate and total nitrogen to validate the model, which limits the validation of the remaining species. Despite the fact that some species are not known a priori, numerical experiments serve as a guide that helps explain how the aquatic ecosystem responds under different initial and boundary conditions. In addition, the PNR curves presented in this research were useful when defining realistic removal rates in a backwater area. BioChemFOAM's ability to formulate scenarios under different driving forces makes the model invaluable in terms of understanding the potential connections between species concentration and flow variables. In general, the case study presents trends in spatial and temporal distributions of non-sampled species that were comparable to measured data.</p>
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Xu, Zhongyan. "A Complex, Linked Watershed-Reservoir Hydrology and Water Quality Model Application for the Occoquan Watershed, Virginia." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/37186.
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The Occoquan Watershed is a 1515 square kilometer basin located in northern Virginia and contains two principal waterbodies: the Occoquan Reservoir and Lake Manassas. Both waterbodies are principal drinking water supplies for local residents and experience eutrophication and summer algae growth. They are continuously threatened by new development from the rapid expansion of the greater Washington D.C. region. The Occoquan model, consisting of six HSPF and two CE-QUAL-W2 submodels linked in a complex way, has been developed and applied to simulate hydrology and water quality activities in the two major reservoirs and the associated drainage areas. The studied water quality constituents include temperature, dissolved oxygen, ammonium nitrogen, oxidized nitrogen, orthophosphate phosphorus, and algae. The calibration of the linked model is for the years 1993-95, with a validation period of 1996-97. The results show that a successful calibration can be achieved using the linked approach, with moderate additional effort. The spatial and temporal distribution of hydrology processes, nutrient detachment and transport, stream temperature and dissolved oxygen were well reproduced by HSPF submodels. By using the outputs generated by HSPF submodels, the CE-QUAL-W2 submodels adequately captured the water budgets, hydrodynamics, temperature, temporal and spatial distribution of dissolved oxygen, ammonium nitrogen, oxidized nitrogen, orthophosphate phosphorus, and algae in Lake Manassas and Occoquan Reservoir. This demonstrates the validity of linking two types of state of the art water quality models: the watershed model HSPF and the reservoir model CE-QUAL-W2.
One of the advantages of the linked model approach is to develop a direct cause and effect relationship between upstream activities and downstream water quality. Therefore, scenarios of various land use proposals, BMP implementation, and point source management can be incorporated into HSPF applications, so that the CE-QUAL-W2 submodels can use the boundary conditions corresponding with these scenarios to predict the water quality variations in the receiving waterbodies. In this research, two land use scenarios were developed. One represented the background condition assuming all the land covered by forest and the other represented the environmental stress posed by future commercial and residential expansion. The results confirm the increases of external nutrient loads due to urbanization and other human activities, which eventually lead to nutrient enrichment and enhanced algae growth in the receiving waterbodies. The increases of external nutrient loads depend on land use patterns and are not evenly spread across the watershed. The future development in the non urban areas will greatly increase the external nutrient production and BMPs should be implemented to reduce the potential environmental degradation. For the existing urban areas, the model results suggest a potential threshold of nutrient production despite future land development. The model results also demonstrate the catchment function of Lake Manassas in reducing nutrient transport downstream.<br>Ph. D.
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Takkouk, Saddek. "Applications of hydrodynamic and water quality models to the Sau and Boadella Reservoirs." Doctoral thesis, Universitat de Girona, 2011. http://hdl.handle.net/10803/31853.
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Applicaciò d'un model de hydrodinàmica i de qualitat de l'aigua als embassaments de Sau i Boadella<br>The aim of this work is to have an idea about the behaviour of Sau and Boedella reservoirs in term of hydrodynamic and water quality, the models applied for are Dynamic simulation model DYRESM and water quality model CAEDYM.<br>En la tesi s'ha aplicat el model de qualitat de l'aigua DYREM-CAEDYM als embassaments de Sau i Boadella. Els models de qualitat de l'aigua són capaços de predir l'evolució física, química i biològica dels embassaments. Un cop inicialitzats i calibrats ens poden donar informació de com evolucionarà, per exemple, el fòsfor dissolt i les poblacions d'algues. Per funcionar, aquests models necessiten nodrir-se diàriament amb dades meteorològiques com ara la radiació solar, la velocitat del vent o les
precipitacions, les quals es poden obtenir d'estacions meteorològiques properes als embassaments. També calen dades biològiques que han estat facilitades per diferents persones i organismes com el Departament d'Ecologia de la Universitat de Barcelona i l'Agència Catalana de l'Aigua. Aquests models no són fàcils de manejar i el primer que s'ha de fer és estudiar-ne
la seva aplicabilitat. Concretament, cal saber si poden ser d'una dimensió o en cal un nombre superior. Això es fa comprovant l'evolució de diferents nombres adimensionals, com per exemple els de Wedderburn i Burger.
Un cop calibrat, el model DYRESM-CAEDYM prediu -molt bé- l'evolució de la temperatura i -bastant bé- la de l'oxigen dissolt, sobretot a l'embassament de Sau,indicant la presència de zones anòxiques al fons. La tendència en l'evolució del
fòsfor dissolt també s'hi veu ben reflectida. En canvi, les simulacions de la clorofila-a, indicativa de les algues, no són tan
acurades ja que depenen de molt factors, alguns dels quals no queden prou reflectits en el model.
L'objectiu final de la tesi és poder millorar la gestió dels embasaments indicant, per exemple, quina és la fondària òptima d'extracció de l'aigua.
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Kumar, Saurav. "An Environmental Decision Support System to Facilitate Stakeholder Interaction with Water Quality Models." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/49399.
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Environmental management has increasingly become a participatory process. In recent times, emphasis has been placed on watershed-based solutions to remediate the problems of diffuse source pollution and to engage stakeholders in designing solutions. Water quality models are an integral part of this process; such models are often inaccessible to lay stakeholders. A review of the literature suggests that properly applied partnerships have several benefits that go beyond decision-making. Stakeholder education and enhancements to the eventual outcome from stakeholder insight and support are two such benefits. To aid engineers and scientists, who often do not interact directly with other stakeholders, several best practices were identified that may be applied to develop, manage, and evaluate stakeholder partnerships.
Environmental Decision Support Systems (EDSSs) have been shown to be an effective way to promote stakeholder partnerships in environmental decision-making. Many current EDSSs were designed to be used by experts, thus limiting their effectiveness for stakeholder engagement. Often, these EDSSs, if designed for lay stakeholders, were not coupled with water quality models. To demonstrate that complex water quality models may be made accessible to stakeholders, without any significant changes to the modeling scheme, a web-based EDSS was developed for the Occoquan Reservoir, located in northern Virginia, U.S.A., and its tributary watershed. The developed EDSS may also be readily extended to other watersheds and their modeling programs.
The current implementation of the EDSS enables users to modify land use and analyze simulated changes to water quality due to these modifications. A local-network server cluster, based on the Locally Distributed Simultaneous Model Execution (LDSME) framework, was also developed and served as a backend to the EDSS. The server cluster can support simultaneous execution of multiple water quality models or any other software on disparate computers. This system was employed to study pre-development and other land use modification scenarios in the Occoquan Watershed.
The pre-development scenario offers an easy-to-understand and universally-applicable baseline for measuring waterbody and watershed restoration progress. It enabled computation of a measure called the "developed-excess," which is independent of local conditions and may be used for comparisons among various watershed sub-divisions or between watersheds.<br>Ph. D.
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Feleke, Arega Woldemariam. "A diagenetic two-layer eutrophication model for Tolo Harbour, Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31241657.
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Jones, Philip Edward James. "Evaluation of water distribution system monitoring using stochastic dynamic modeling." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/40441.
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A stochastic dynamic constituent transport model was developed, capable of simulating the operation of a water distribution system containing pumps and storage tanks, and subject to random demands and contaminant inputs. Long term operation of a hypothetical small town water supply system containing one pump station and one storage tank was simulated while the system was subjected to external contaminant inputs. Repeated simulations were made under different regimes of external contamination applied to the tank, the pump station and at system nodes, and internal contamination representing biofilm effects based on assumed relationships between flow velocities and bioflim cell detachment. Seven sampling plans representing regulatory requirements and industry practice were applied during the simulation to evaluate their ability to detect the contamination under a presence/absence criterion.
The simulations were able to identify contamination patterns and provide information useful in the definition of sampling plans. Time of sampling was found to be as important as location. This was true both within the monitoring period, and particularly within the diurnal cycle of demand. Spreading samples over different days within the monitoring period rather than sampling all on one day, always improved contaminant detection. Detection by plans based on fixed times and locations were very sensitive to those times and locations.
There was no best plan suitable for all situations tested. The better sampling plans were those that captured the temporal and spatial contamination patterns present in the system. No consistent advantage was noted from sampling in proportion to population served or in locating sampling nodes systematically instead of randomly. The location and timing of sampling for most plans could be improved with the knowledge of actual contamination patterns and timing provided by the model.
The presence of a storage tank was found to have a strong influence on hydraulic patterns and the location and timing of contamination reaching different parts of the system.<br>Ph. D.
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Al, Kasbi Mohammed. "Assessing water quality in Sultanate of Oman using a newly developed dynamic speciation technique." Thesis, Lancaster University, 2016. http://eprints.lancs.ac.uk/80278/.
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Rapid increases in coastal developments in the Sultanate of Oman recently, including large ports with industries, crude oil refineries, mining and industrial activities, have often produced point sources of metal and organic contaminations in the local marine systems. Although advances have been made in measuring and understanding the trace metal speciation in aquatic system using a dynamic technique DGT (Diffusive Gradients in Thin-films) or using other equilibrium techniques, measuring metal speciation in situ in seawater that polluted by crude oil is still extremely challenging. Without the technology and the information, it is difficult to assess the effects of oil ligands on metal speciation associated with the oil refineries and industries. In the present study, the DGT technique has been developed further for measuring metal speciation in seawaters in the presence of oil. The influence of oil ligands on the speciation of trace metals (Cd, Co, Cu, Ni, Pb and Zn) has been investigated in synthetic solutions of 0.5 and 0.7 mol/L NaCl containing different level of Oman crude oil. DGT of different types in diffusive layers (pore size and thicknesses), binding layers (Chelex resin and Fe oxide) and different types of membranes (dialysis membranes (1000 MWCO and 3500 MWCO) and 0.05 mm thickness Nafion112 membrane) were used. The diffusion coefficients were determined for each metal, using a diffusion cell, through filter membrane and diffusive gel with and without dialysis and Nafion112 membranes. The measured diffusion coefficients of all metals in diffusive gel plus dialysis membrane were significantly lower than gel alone. When Nafion112 membrane wasused with the diffusive gel, the diffusion coefficients of all metals were much lower,up to 80 times lower for Cu, Cd and Ni. The potential of using DGT for determining labile metals species in seawater in the presence of crude oil was evaluated in mixed solution of NaCl and oil with varying mixing periods (0.25 day, 0.5 day, 1 day, 2 days, 4 days and 6 days) and oil concentrations (1, 3, 5, 7, 25 OWR% (oil water ratio), w/v). It was demonstrated that organic ligands from crude oil influenced the lability of trace metals. The combination of five types of DGT devices (OP-DGT, RG-DGT, (dialysis 1000Da)-DG, (dialysis 3500Da)-DGT, (Nafion 112)-DGT) were used for speciation of metals at 1 and 4 oil water ratio (OWR%), and 48 h mixing time. Lower concentrations of labile metals were determined with the higher level of oil in the synthetic solution when using Nafion 112-DGT, due to the exclusion of large colloids and negatively charged metal complexes by Nafion 112 membrane. No significance differences were observed between OP-DGT and RG-DGT for Co, Ni, Zn and Pb at 1% OWR and Co, Ni and Pb in at 4% OWR. This suggests the labile complexes of metals and organic ligands from oil may be smaller than the pore size of the restricted diffusive gel. Comparing (Dialysis 1000MWCO)-DGT and 1000MWCO- Micro Float microdialysis measurements indicated that Co, Cd, Cu and Zn were complexed with ligands small enough to pass through the 1000 MWCO- Micro Float microdialysis but not labile enough to be retained in the (Dialysis 1000 MWCO)-DGT samplers. DGT technique was applied to soils contaminated with both metals and crude oil to evaluate the effect of oil level and aging on the availability of metals in soils. The dissolved metals in soil solution (Csoln), labile concentrations by DGT (CDGT) and extractable concentration by CaCl2 were measured. Values of labile pool size, Kd, and R (ratio of CDGT and Csoln) were calculated and the kinetic parameters (response time Tc and desorption rate k−1) were obtained using DIFS (DGT Induced Fluxes in Soils and sediments) model. Increases of crude oil treatments in soils promoted the formation of non-labile species of Cu and Pb and limited the availability of both metals. The time scales of the kinetic exchanges obtained from DGT measurements and DIFS modelling was reflected by the range of determined Tc values: from seconds to 3 hours. The gradual decrease of Kd values for Cu with time in three studied soils with and without oil application may be attributed to the strong tendency of Cu to be associated with the solid phase with increasing incubation time. The Kd values of Ni were generally decreased with adding of crude oil amendments in three soils may be due to the release of Ni species from solid phase and crude oil to soil solution. Three soils were resupply of Cd and Pb in general very slow to measure. The generally slower release rates of Cd and Pb compared to other studied metals may reflect the lower concentration of Cd and Pb which allowed a higher proportion of them to associate strongly with organic ligands sites with slower release rates. The trend changes for k-1 values of studied metals in three selected soils were influenced by crude oil amendments and aging time. All developed DGT of different types, including DGT with ferrihydrite for oxyanions (As, Se, Mo, V, Sb and W), were deployed in situ in seawater and groundwater around refineries and industrial areas in Oman. Soils and sediments in those areas were also collected for DGT deployments. The labile concentrations of Cr, Co, Ni, Cu, Cd, and Pb were generally low and not significantly different at all the sampling locations due to the formation of strong metals complexes with organic ligands that are less labile. The measured concentrations of labile V in all selected locations were much lower than the total V concentration in the filtered grab samples (CSol (0.45 μm filtered)) due to high levels of large colloidal ligands from crude oil. The low proportion of Ni labile species (11%-29%) was measured by (Nafion112)-DGT in all selected open wells because Ni is mainly complexed by negatively charged ligands and they were excluded by Nafion112 membrane. The labile Fe, Ni and Mn concentrations in Wells-1 and -2 were much higher than those in Well-3 and (RIE)’swells reflecting the occurrence of more intense oil and industrial contamination in the area. For coastal sediments near the refinery discharge point at Al Fahal port, the DGT measured labile concentrations of Fe, Ni, Cu, and V were higher near the discharge point. The DGT concentrations of Al, Fe and Mn in soils collected from SIR ranged from (12-22 μg/L), (14-63 μg/L) and (9-17μg/L) respectively, in line with the background level of those metals. For 15 selected soils, their Kd ranged from (1.8-33) ml/g for (Al, Cr, Mn, Fe, Ni and Cu). The Kd values of Pb were higher at soil locations (L2, L7, L8 and L11) of 266, 65, 43 and 55 gm/L respectively due to the higher metal retention by the solid phase through sorption reactions and low concentration in the soil solution. The obtained results suggest that risk assessment of sandy soils could be carried out using measurements of metals in soil solutions. However, devices such as DGT dynamic technique, which respond to the kinetics of supply, are essential to evaluate available metal in high pH and crude oil contaminated soils. Because DGT is a dynamic technique and it can be readily deployed in situ, in seawaters, groundwaters, soils, and sediments, it provides kinetic information directly in crude oil contaminated environmental systems and allows better understanding and risk assessments.
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Chadik, Paul Arthur. "Modeling trihalomethane formation in drinking water after alum coagulation or activated carbon adsorption." Diss., The University of Arizona, 1985. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1985_293_sip1_w.pdf&type=application/pdf.
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Amin, Muhammad Anjum. "Predicting the variations in water quality along an irrigation canal in Punjab, Pakistan." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32750.
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The Indus Basin Irrigation System (IBIS) irrigates 16 million ha of land in Pakistan. The irrigation water is also used for domestic consumption in rural areas and where the ground water is brackish. Many major cities and towns dispose their untreated wastewater directly into the irrigation canal network, which ultimately has adverse impacts on the downstream water quality. In order to better understand the water quality variations, several parameters were measured along a 45 km long irrigation canal (Hakra-6R) in Punjab, Pakistan during the year 2000. The parameters measured were: biochemical oxygen demand (BOD), nitrate (NO3), ammonia (NH3), Escherichia coli (E.coli), dissolved oxygen (DO), pH, and water temperature. The PC-QUASAR model was used as predictive tool to simulate the water quality concentrations along the downstream locations of Hakra-6R canal. The measured data were used to validate the PC-QUASAR model. The model efficiencies ranged from 0.40 to 0.96 for selected parameters. A sensitivity analysis showed that the nitrification, denitrification, BOD sedimentation, and BOD algae rate were the most sensitive parameters of model performance. The BOD decay and sediment oxygen rates have negligible influence on model output. Water quality analysis showed that irrigation water was highly contaminated regarding microbiological aspects (E.coli ∼ 4000 N/100ml).
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Slaughter, Andrew Robert. "Modelling the relationship between flow and water quality in South African rivers." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1006196.
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The National Water Act (Act 36 of 1998) provides for an ecological Reserve as the quantity (flow) and quality of water needed to protect aquatic ecosystems. While there are methods available to quantify the ecological Reserve in terms of flow, methods of linking flow to water quality are lacking. Therefore, the research presented in this thesis investigated various modelling techniques to estimate the effect of flow on water quality. The aims of the research presented in this thesis were: Aim 1: Can the relationship between flow and water quality be accurately represented by simple statistical models? Aim 2: Can relatively simple models accurately represent the relationship between flow and water quality? Aim 3: Can the effect of diffuse sources be omitted from a water quality model and still obtain realistic simulations, and if so under what conditions? Aim 4: Can models that solely use historical monitoring data, accurately represent the relationships between flow and water quality? In Chapter 3, simple Q-C regressions of flow and water quality were investigated using Department of Water Affairs (DWA) historical monitoring data. It was found that while flow versus salinity regressions gave good regression fits in many cases, the Q-C regression approach is limited. A mechanistic/statistical model that attempted to estimate the point and diffuse signatures of nutrients in response to flow was developed in Chapter 4 using DWA historical monitoring data. The model was verified as accurate in certain case studies using observed point loading information. In Chapter 5, statistical models that link land cover information to diffuse nutrient signatures in response to flow using DWA historical data were developed. While the model estimations are uncertain due to a lack of data, they do provide an estimation of the diffuse signature within catchments where there is flow and land cover information available. Chapter 6 investigates the extension of an existing mass-balance salinity model to estimate the effect of saline irrigation return flow on in-stream salinity. The model gave accurate salinity estimates for a low order stream with little or no irrigation within its catchment, and for a permanently flowing river within a catchment used extensively for irrigation. Chapter 7 investigated a modelling method to estimate the reaction coefficients involved in nitrification using only DWA historical monitoring data. Here, the model used flow information to estimate the residence time of nutrients within the studied river reaches. While the model obtained good estimations of nitrification for the data it was applied to, very few DWA data sets were suitable for the model. Chapter 8 investigated the ability of the in-stream model QUAL2K to estimate nutrient concentrations downstream of point and diffuse inputs of nutrients. It was found that the QUAL2K model can give accurate results in cases where point sources dominate the total nutrient inputs into a river. However, the QUAL2K simulations are too uncertain in cases where there are large diffuse source inputs of nutrients as the load of the diffuse inputs is difficult to measure in the field. This research highlights the problem of data scarcity in terms of temporal resolution as well as the range of constituents measured within DWA historical monitoring data for water quality. This thesis in addition argues that the approach of applying a number of models is preferable to applying one model to investigate the research aims, as particular models would be suited to particular circumstances, and the development of new models allowed the research aims of this thesis to be explored more thoroughly. It is also argued that simpler models that simulate a few key processes that explain the variation in observed data, are more suitable for implementing Integrated Water Resource Management (IWRM) than large comprehensive water quality models. From this research, it is clear that simple statistical models are not adequate for modelling the relationship between flow and water quality, however, relatively simple mechanistic models that simulate a limited number of processes and water quality variables, can provide accurate representations of this relationship. Under conditions where diffuse sources are not a major factor within a catchment, models that omit diffuse sources can obtain realistic simulations of the relationship between flow and water quality. Most of the models investigated in this thesis demonstrate that accurate simulations of the relationships between flow and water quality can be obtained using solely historical monitoring data.
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Smit, Jacobus Petrus Johannes. "The quantification of prediction uncertainty associated with water quality models using Monte Carlo Simulation." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85814.
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Thesis (MEng)--Stellenbosch University, 2013.<br>ENGLISH ABSTRACT: Water Quality Models are mathematical representations of ecological systems and they play a major role in the planning and management of water resources and aquatic environments. Important decisions concerning capital investment and environmental consequences often rely on the results of Water Quality Models and it is therefore very important that decision makers are aware and understand the uncertainty associated with these models. The focus of this study was on the use of Monte Carlo Simulation for the quantification of prediction uncertainty associated with Water Quality Models.
Two types of uncertainty exist: Epistemic Uncertainty and Aleatory Uncertainty. Epistemic uncertainty is a result of a lack of knowledge and aleatory uncertainty is due to the natural variability of an environmental system. It is very important to distinguish between these two types of uncertainty because the analysis of a model’s uncertainty depends on it. Three different configurations of Monte Carlo Simulation in the analysis of uncertainty were discussed and illustrated: Single Phase Monte Carlo Simulation (SPMCS), Two Phase Monte Carlo Simulation (TPMCS) and Parameter Monte Carlo Simulation (PMCS). Each configuration of Monte Carlo Simulation has its own objective in the analysis of a model’s uncertainty and depends on the distinction between the types of uncertainty.
As an experiment, a hypothetical river was modelled using the Streeter-Phelps model and synthetic data was generated for the system. The generation of the synthetic data allowed for the experiment to be performed under controlled conditions. The modelling protocol followed in the experiment included two uncertainty analyses. All three types of Monte Carlo Simulations were used in these uncertainty analyses to quantify the model’s prediction uncertainty in fulfilment of their different objectives.
The first uncertainty analysis, known as the preliminary uncertainty analysis, was performed to take stock of the model’s situation concerning uncertainty before any effort was made to reduce the model’s prediction uncertainty. The idea behind the preliminary uncertainty analysis was that it would help in further modelling decisions with regards to calibration and parameter estimation experiments. Parameter uncertainty was reduced by the calibration of the model. Once parameter uncertainty was reduced, the second uncertainty analysis, known as the confirmatory uncertainty analysis, was performed to confirm that the uncertainty associated with the model was indeed reduced. The two uncertainty analyses were conducted in exactly the same way.
In conclusion to the experiment, it was illustrated how the quantification of the model’s prediction uncertainty aided in the calculation of a Total Maximum Daily Load (TMDL). The Margin of Safety (MOS) included in the TMDL could be determined based on scientific information provided by the uncertainty analysis. The total MOS assigned to the TMDL was -35% of the mean load allocation for the point source. For the sake of simplicity load allocations from non-point sources were disregarded.<br>AFRIKAANSE OPSOMMING: Watergehalte modelle is wiskundige voorstellings van ekologiese sisteme en speel ’n belangrike rol in die beplanning en bestuur van waterhulpbronne en wateromgewings. Belangrike besluite rakende finansiële beleggings en besluite rakende die omgewing maak dikwels staat op die resultate van watergehalte modelle. Dit is dus baie belangrik dat besluitnemers bewus is van die onsekerhede verbonde met die modelle en dit verstaan. Die fokus van hierdie studie het berus op die gebruik van die Monte Carlo Simulasie om die voorspellingsonsekerhede van watergehalte modelle te kwantifiseer.
Twee tipes onsekerhede bestaan: Epistemologiese onsekerheid en toeval afhangende onsekerheid. Epistemologiese onsekerheid is die oorsaak van ‘n gebrek aan kennis terwyl toeval afhangende onsekerheid die natuurlike wisselvalligheid in ’n natuurlike omgewing behels. Dit is belangrik om te onderskei tussen hierdie twee tipes onsekerhede aangesien die analise van ’n model se onsekerheid hiervan afhang. Drie verskillende rangskikkings van Monte Carlo Simulasies in die analise van die onsekerhede word bespreek en geïllustreer: Enkel Fase Monte Carlo Simulasie (SPMCS), Dubbel Fase Monte Carlo Simulasie (TPMCS) en Parameter Monte Carlo Simulasie (PMCS). Elke rangskikking van Monte Carlo Simulasie het sy eie doelwit in die analise van ’n model se onsekerheid en hang af van die onderskeiding tussen die twee tipes onsekerhede.
As eksperiment is ’n hipotetiese rivier gemodelleer deur gebruik te maak van die Streeter-Phelps teorie en sintetiese data is vir die rivier gegenereer. Die sintetiese data het gesorg dat die eksperiment onder beheerde toestande kon plaasvind. Die protokol in die eksperiment het twee onsekerheids analises ingesluit. Al drie die rangskikkings van die Monte Carlo Simulasie is gebruik in hierdie analises om die voorspellingsonsekerheid van die model te kwantifiseer en hul doelwitte te bereik.
Die eerste analise, die voorlopige onsekerheidsanalise, is uitgevoer om die model se situasie met betrekking tot die onsekerheid op te som voor enige stappe geneem is om die model se voorspellings onsekerheid te probeer verminder. Die idee agter die voorlopige onsekerheidsanalise was dat dit sou help in verdere modelleringsbesluite ten opsigte van kalibrasie en die skatting van parameters. Onsekerhede binne die parameters is verminder deur die model te kalibreer, waarna die tweede onsekerheidsanalise uitgevoer is. Hierdie analise word die bevestigingsonsekerheidsanalise genoem en word uitgevoer met die doel om vas te stel of die onsekerheid geassosieer met die model wel verminder is. Die twee tipes analises word op presies dieselfde manier toegepas.
In die afloop tot die eksperiment, is gewys hoe die resultate van ’n onsekerheidsanalise gebruik is in die berekening van ’n totale maksimum daaglikse belading (TMDL) vir die rivier. Die veiligheidgrens (MOS) ingesluit in die TMDL kon vasgestel word deur die gebruik van wetenskaplike kennis wat voorsien is deur die onsekerheidsanalise. Die MOS het bestaan uit -35% van die gemiddelde toegekende lading vir puntbelasting van besoedeling in die rivier. Om die eksperiment eenvoudig te hou is verspreide laste van besoedeling nie gemodelleer nie.
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Thoe, Wai, and 陶煒. "Integrated river management of the East River: field studies, hydrologic and water quality modelling." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38997575.
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Heller, Winfried [Verfasser]. "Hydro-dynamic effects with particular consideration of water quality and their measurement methods / Winfried Heller." Tönning, 2005. http://d-nb.info/979397405/34.
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Keogh, Andrew James, University of Western Sydney, of Science Technology and Environment College, and School of Engineering and Industrial Design. "Geo-chemical budget models of the Penrith Lakes Scheme." THESIS_CSTE_EID_Keogh_A.xml, 2003. http://handle.uws.edu.au:8081/1959.7/472.
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The Penrith Lakes Scheme is a series of inter-connected lakes, produced by the rehabilitation of a sand and gravel quarry, for water quality treatment and recreational uses. Presently, 5 lakes are operational comprising 4 upstream lakes for treatment of storm-water and quarry discharge and a single downstream recreational lake as the Sydney International Regatta Centre used during the Sydney 2000 Olympic Games. This report is the result of a study, during 1998-2003, with an aim to develop dynamic budget models of water, sediments and nutrients for these lakes, providing suitable data for long-term management planning and evaluation of short-term operational management.Findings showed that while progressive reassessment and refinement will be required as management control increases, the approach provides the foundation modelling procedures and frame-work for suitable hydrological and water quality management of the Penrith Lakes Scheme, and may be extended to include further lakes, water sources and management strategies.<br>Doctor of Philosophy (PhD)
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Gollamudi, Apurva. "Hydrological and water quality modeling of agricultural fields in Quebec." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98710.
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Two tile-drained agricultural fields in the Pike River watershed of Southern Quebec were instrumented in October 2000 to monitor phosphorus and nitrate concentrations in surface runoff and tile drainage. Data collected from these sites were used as the primary input to test a GIS-based hydrological and water quality simulation model (ArcView SWAT2000) at the field scale. Surface runoff, subsurface flow, sediment yield, nitrate loads and phosphorus loads were the principal parameters evaluated by the model. The SWAT model was calibrated using data collected in the year 2002 while 2003 data was used for validating the model. Particulate phosphorus and total dissolved phosphorus loads in streamflow were also simulated using SWAT and compared with field measurements.<br>A sensitivity analysis showed that curve number, available soil water content and soil evaporation factors significantly influenced water yield simulations while model performance for water quality parameters was governed mainly by the accuracy of simulating field operations such as fertilization and tillage. The monthly coefficients of performance after calibration ranged from being very good for some parameters (0.27 to 0.66 for total water yield; 0.38 to 0.67 for total phosphorus; and 0.23 to 0.89 for sediments) to being inconsistent for others (0.44 to 2.28 for subsurface flow; 0.63 to 4.36 for surface runoff; and 0.66 to 1.35 for total nitrate loads). Overall, it was found that SWAT results on a seasonal scale were generally more reliable whereas daily or monthly simulations could be improved by using a longer calibration period or incorporating model changes. Short-term impacts of implementing different best management practices for tillage, crop rotation and fertilization were also evaluated using the validated SWAT model. It was found that conservation tillage of corn coupled with pasture or soybean rotations can reduce total phosphorus loads in the range of 25-50% over conventional tillage with corn.
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Xu, Wenwei. "Development of a Steady-State River Hydrodynamic and Temperature Model Based on CE-QUAL-W2." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1619.
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CE-QUAL-W2 is a 2-D hydrodynamic and water quality model that has been applied to reservoirs, lakes, river systems, and estuaries throughout the world. However, when this model is applied for shallow systems, this model requires a long calculation time to maintain numerical stability, compared to applications of reservoirs or deeper river systems.
To solve this problem, a new hydrodynamic and temperature model was built based on the framework of CE-QUAL-W2 but that allows for steady-state hydrodynamic computations. By calculating the hydrodynamics at steady-state, the time step for stability is relaxed and simulations can proceed at much higher time steps. The rest of the model framework is still used for water quality state variables, in this case, temperature. The algorithm used for computing the water surface elevation is Manning's equation.
This thesis study is one part of the Willamette Water 2100 project (Santelmann et al., 2012), which examines hydrological, ecological, and human factors affecting water scarcity in the Willamette River Basin. This study included three stages: (1) Convert six existing CE-QUAL-W2 V3.1 models into a newer version: CE-QUAL-W2 V3.7. (2) Develop the steady-state model code in FORTRAN. (3) Test the steady-state model on three river systems in the Willamette River Basin at Year 2001 and 2002.
The result proved that the steady-state model could reduce the computing time by 90% for river applications, while predicting dynamic river temperature with high accuracy at a two-minute time scale. This new model will be employed to simulate the future of the Willamette River System at a decadal or centennial timescales, addressing river temperature concerns and fish habitat issues.
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LEE, YEONGHO. "MASS DISPERSION IN INTERMITTENT LAMINAR FLOW." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1085750678.
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Harvey, Robert Richard. "Statistical regression models and control charts for the real time water quality network in Newfoundland/." Internet access available to MUN users only. Search for this title in:, 2009.
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May, Annabelle. "An assessment of the impact of regulatory models for drinking water quality in the UK." Thesis, University of Surrey, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443384.
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Gadipudi, Rao K. "Evaluating the effects of agricultural practices on water quality by interfacing GIS with computer models." FIU Digital Commons, 1994. http://digitalcommons.fiu.edu/etd/3431.
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Nonpoint source pollution from agricultural activities significantly impacts quality of receiving water bodies, including increases in stream sediments and nutrients, and occurrence of pesticides in both surface and ground water. Agricultural activities in the West Wellfield Interim Protection Area (WWIPA), located in West Dade County in South Florida, have potential to impact both the environmentally sensitive Everglades and Florida Bay, and the Biscayne aquifer. The Hydrological Simulation Program-Fortran (HSPF) has been used to simulate water and constituent transport in the WWIPA and to determine possible impacts. Surface runoff, groundwater recharge, and transport of sediments, nutrients and pesticides are simulated by this model. ARC/INFO Geographic Information Systems (GIS) is interfaced with HSPF to store, manage, and display data, and derive input parameters for the model. Results of HSPF simulations are also visually presented through GIS. A GIS user interface was developed for the study area. Menus were created through which the database can be queried to derive model parameters and to visually present results through maps. Model results show that sediments, nutrients and pesticides are present in surface runoff, and nutrients enter the ground water. Various model test runs were made to minimize pollution levels without hindering agricultural production. They include application of minimum required rates of fertilizers, replacement of fertilizers by sewage sludge, and the effect of future urbanization.
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Al-Zubaidi, Hussein Ali Mahdi. "3D Hydrodynamic, Temperature, and Water Quality Numerical Model for Surface Waterbodies: Development, Verification, and Field Case Studies." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4500.
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Numerical modeling has become a major tool for managing water quality in surface waterbodies such as rivers, lakes, reservoirs, and estuaries. Since the two-dimensional longitudinal/vertical model CE-QUAL-W2 is a well-known model and it has been applied to thousands of waterbodies around the world successfully, its numerical scheme was adapted to develop a new three-dimensional numerical model for simulating hydrodynamics, temperature, and water quality in surface waterbodies. Finite difference approximations were used to solve the fluid dynamic governing equations of continuity, free water surface, momentums, and mass transport. No coordinate transformations were performed and the z-coordinate system has been used. Higher-order schemes (QUICK, QUICKEST, and ULTIMATE QUICKEST) in addition to the UPWIND scheme were used for the advective temperature and mass transport. A novel numerical approach was used for the numerical formulation of the three-dimensional scheme. This approach forced the numerical solution of the free surface equation to be a tri-diagonal matrix form rather than a more computationally intensive penta-diagonal matrix solution. This new approach was done by linking a method called line-by-line with the free water surface numerical solution. Another new approach was that the three-dimensional numerical scheme involved a simultaneous solution of hydrodynamics, temperature, and water quality at every model time level instead of saving the hydrodynamic results to be used later for water quality simulation. Hence, this scheme allowed feedback between the hydrodynamics and water quality every time step. In addition, various unique numerical algorithms were employed from CE-QUAL-W2 such as the W2 turbulence model, selective withdrawal theory, surface heat fluxes, and water quality sources and sinks, making the three-dimensional model built on well-tested algorithms.
To test the model structure and assumptions, an analytical verification was performed by comparing model predictions to known analytical exact solutions test cases. Good agreement was showed by the model for all of these tests. A computation of the volume balance over the simulation period was also incorporated within the model to assess how well the code performed. Sensitivity tests were also made varying bed and wind shear.
The model was also applied to three reservoirs in the USA as field case studies: Lake Chaplain in WA, Laurance Lake in OR, and Cooper Creek Reservoir in OR. The model was validated by comparing the model predictions of water levels, velocities, vertical temperature profiles, and dissolved oxygen with field data. Through these real applications, the numerical predictions of the 3D model showed good agreement with field data based on error statistics. The model results of each field case study were discussed separately. In the Lake Chaplain model application, the study was focused on the importance of the higher-order schemes compared to the first-order UPWIND scheme. The model predictions of temperature were determined by using the UPWIND, QUICK, and QUICKEST scheme and compared with field data. The Error statistics of the model predictions compared to field data were an absolute mean error (AME) of 0.065 m for the water level predictions and an overall AME of 1.62 °C, 1.09 °C, and 1.23 °C for the temperature predictions by using the UPWIND, QUICK, and QUICKEST scheme, respectively. In the Laurance Lake model application, a comparison was performed between the present 3D model and the 2D CE-QUAL-W2. Since the 3D model was build based on CE-QUAL-W2, differences between the two models were evaluated. Error statistics between the model predictions of water level and temperature compared to field data showed that both models were in good agreement with field data. However, the 3D model AME (0.30 m for the water level predictions and 0.48 °C for the temperature predictions) was higher than the 2D model (0.03 m for the water level predictions and 0.42 °C for the temperature predictions). Finally, the Cooper Creek Reservoir case study was done to show the model predictions of temperature and dissolved oxygen. In this application, vertical temperature profiles were covered the entire simulation period in order to show how the model transfer heat between stratification and non- stratification conditions. The model showed good agreement with field data (0.12 m AME for the water level predictions, 1.00 °C overall AME for the temperature predictions, and 1.32 g/m3 overall AME for the dissolved oxygen predictions).
Finally, comparisons were made between CE-QUAL-W2 and the 3D model. The 2D model generally performed better in the tests cases if the model user is unconcerned about lateral impacts. The 3D model is important to use when lateral currents and variation in the lateral dimension are important.
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Wu, Yiping, and 吴一平. "Investigation of integrated terrestrial processes over the East River basin in South China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43085799.
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Dube, Renias Admore. "Appropriate positioning of modelling as a decision support tool for surface water resources planning in South Africa." Thesis, Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-08242006-122230.
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Thesis (Ph.D) (Microbiology and Plant Pathology)--University of Pretoria, 2006.<br>Summaries in Afrikaans and English. Includes bibliographical references. Available on the Internet via the World Wide Web.
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Du, Yi. "Implementation of a Wetting and Drying Model in Simulating the Androscoggin/Kennebec Plume and the Circulation in Casco Bay." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/DuY2008.pdf.
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