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Analysis of Cutthroat Flume Discharge RatingsRen, Liyan 01 May 1993 (has links)
Sixteeen sets of original laboratory data collected by many investigators for various Cutthroat flume sizes are thoroughly reviewed and organized. Best-fit discharge parameters are obtained by performing the free-flow analysis and the submerged-flow analysis. Then, the transition submergence can be calculated. Afterwards, the unified free-flow and submerged-flow discharge parameter s are developed for each flume size in order to generalize the calibrations for Cutthroat flumes. This is a very tedious process requiring a trial-and-error approach. Finally, comparisons are made of the measured laboratory discharges with the predicted discharges for both free flow and submerged flow using both the best-fit and the unified discharge parameters.
The results proved quite good as measured by the standard deviation for each flume size. In most cases, the average standard deviation using the unified discharge parameters was only slightly greater than when using the best-fit discharge parameters. However, there is a significant difference in the accuracy of free-flow measurements compared with submerged-flow measurements. Using the unified discharge parameters, the mean standard deviation for all of the flumes was 2.1 percent for free flow and 6.5 percent for submerged flow.
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Instrumentation, model identification and control of an experimental irrigation canalSepúlveda Toepfer, Carlos 03 April 2008 (has links)
This thesis aims to develop control algorithms for irrigation canals in an experimental framework.These water transport systems are difficult to manage and present low efficiencies in practice. As a result, an important percentage of water is lost, maintenance costs increase and water users follow a rigid irrigation schedule.All these problems can be reduced by automating the operation of irrigation canals.In order to fulfil the objectives, a laboratory canal, called Canal PAC-UPC, was equipped and instrumented in parallel with the development of this thesis. In general, the methods and solutions proposed herein were extensively tested in this canal.In a broader context, three main contributions in different irrigation canal control areas are presented.Focusing on gate-discharge measurements, many submerged-discharge calculation methods are tested and compared using Canal PAC-UPC measurement data. It has been found that most of them present errors around ±10%, but there are notable exceptions. Specifically, using classical formulas with a constant 0.611 contraction value give very good results (error<±6%), but when data is available, a very simple calibration formula recently proposed in the literature significantly outperform the rest (error<±3%). As a consequence, the latter is encouragingly proposed as the basis of any gate discharge controller.With respect to irrigation canal modeling, a detailed procedure to obtain data-driven linear irrigation canal models is successfully developed. These models do not use physical parameters of the system, but are constructed from measurement data. In this case, these models are thought to be used in irrigation canal control issues like controller tuning, internal controller model in predictive controllers or simply as fast and simple simulation platforms. Much effort is employed in obtaining an adequate model structure from the linearized Saint-Venant equations, yielding to a mathematical procedure that verifies the existence of an integrator pole in any type of canal working under any hydraulic condition. Time-domain and frequency-domain results demonstrate the accuracy of the resulting models approximating a canal working around a particular operation condition both in simulation and experiment.Regarding to irrigation canal control, two research lines are exploited. First, a new water level control scheme is proposed as an alternative between decentralized and centralized control. It is called Semi-decentralized scheme and aims to resemble the centralized control performance while maintaining an almost decentralized structure. Second, different water level control schemes based on PI control and Predictive control are studied and compared. The simulation and laboratory results show that the response and performance of this new strategy against offtake discharge changes, are almost identical to the ones of the centralized control, outperforming the other tested schemes based on PI control and on Predictive control. In addition, it is verified that schemes based on Predictive control with good controller models can counteract offtake discharge variations with less level deviations and in almost half the time than PI-based schemes.In addition to these three main contributions, many other smaller developments, minor results and practical recommendations for irrigation canal automation are presented throughout this thesis.
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Zatopení nízkých pravoúhlých přelivů se širokou korunou / Submergence of low rectangular sharp-edged broad-crested weirsMajor, Jakub January 2015 (has links)
This diploma thesis deals with submergence of low rectangular sharp-edged broad-crested weirs. From measurement of water levels in front of and behind of weir at different discharges and different weir heights, were determined values of submergence coefficient depending on relative height of submergence. From these values were determined the equation of submergence coefficient. Measured values were compared which results measurements, which are given in professional literature.
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Vliv pdorysn©ho situovn na kapacitu pelivu v prizmatick©m korytÄ / Influence of plan situating of weir in the prismatic channel on discharging capacityLukek, Petr January 2016 (has links)
This diploma thesis is focused on determination of plan situating influence of weir discharging capacity. The part of this work is a summary of the information about weirs, principally about determination of discharging capacity on normal weirs, plan deflected and plan radius weirs. Executed model research, which deals with determination of plan situating influence on discharging capacity plan deflected and plan radius weirs in comparison to normal weir, is evaluated in another part of this work. The research is also dealing with influence of aeration of the space under down surface of free jet and influence of downstream water level on discharging capacity. This work compares the results of executed research with available knowledge of other authors, who have dealt with determination of discharging capacity on weirs with different plan situating.
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Stanovení Q/h charakteristiky přelivů stavidlové komory ČOV Brno-Modřice v podmínkách nedokonalého proudění / Determination of Q/h characteristics of spillways of the sluice chamber of the Brno-Modřice WWTP in conditions of influenced flowŠkrancová, Markéta January 2022 (has links)
The work deal with the measurement, processing and analysis of Q/h characteristics of the sluice chamber in the wastewater treatment plant on a physical hydraulic model in the conditions of influencing the overflow phenomenon by the groundwater level. Based on the achieved results, a measuring system has been projected in the area of the sluice chamber to measure the flow and flow rate of lightened water into the Svratka river. The measurements on the model were performed in the premises of the Laboratory of water Management Research of the Institute of Water Structures of the Faculty of Civil Engineering of Brno University of Technology by the author of this work. The results of the diploma thesis is a flow chart describing the calculation procedure used to determine the immediate flow, on the basis of which a new software of the evaluation unit of the measuring system was realized.
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