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1
Yapa, Poojitha D., Hung Tao Shen, Steven F. Daly, and Stephen C. Hung. "Oil Spill Simulation in Rivers." International Oil Spill Conference Proceedings 1991, no. 1 (March 1, 1991): 593–600. http://dx.doi.org/10.7901/2169-3358-1991-1-593.
Повний текст джерелаАнотація:
ABSTRACT Computer models recently have been developed for simulating oil slick transport in rivers, including the connecting channels of the Great Lakes, the upper St. Lawrence River, and the Allegheny-Monongahela-Ohio River system. In these models, a Lagrangian discrete-parcel algorithm is used to determine the location and concentration distribution of the oil in the river as well as the deposition of oil on the shore. The model for the Great Lakes connecting channels (ROSS) is a two-dimensional surface slick model which considers advection, spreading, horizontal diffusion, evaporation, dissolution, and shoreline deposition. The model is applicable to both open water and ice covered conditions. Models for the St. Lawrence River and the Ohio River System are developed based on a two-layer scheme (ROSS2) which considers vertical mixing and emulsiflcation processes in addition to the processes considered in the surface slick model. All of these models are implemented on microcomputers and can be used as integral parts of oil spill response programs to assist cleanup actions.
2
Shokirov, B., B. Norkulov, Kh Nishanbaev, M. Khurazbaev, and B. Nazarov. "Computer simulation of channel processes." E3S Web of Conferences 97 (2019): 05012. http://dx.doi.org/10.1051/e3sconf/20199705012.
Повний текст джерелаАнотація:
The article discusses the results of numerical studies of flow movement with a sharp change in the channel parameters. The numerical study of the flow in the channels and rivers creates the possibility of a multivariate forecast of channel processes, rivers, and requires minimal expenditures. The purpose of the study is to determine the main objectives and directions of research in the area under consideration. A mathematical model and a computer program have been developed that allow solving a wide range of tasks for modelling currents in the channels of various difficulties, taking into account daily regulation. This makes it possible to identify and proactively take measures, such as: determining the time to reach the flow along the channel; the establishment of water volume flow in an arbitrary channel; taking emergency measures to regulate the incoming residual volume of water after its termination into the system, in the event of an accident at pumping stations; identification of the nature and direction of channel processes; prevention of undermining of supports and damage to power lines passing through the channel, and many other engineering tasks. The developed tested mathematical model allows in real conditions and in real time to help the operational services of large channels in the operational management of actions, in emergency situations, and the choice of the most effective, at any point in time, measures to minimize the consequences. Analysis of the results of many researchers has created the opportunity for the authors of this article to conclude that the above system of hydrodynamic equations is applicable in mathematical modelling of motion, taking into account the transverse circulation of the flow.
3
Nikora, Vladimir I., Victor B. Sapozhnikov, and David A. Noever. "Fractal geometry of individual river channels and its computer simulation." Water Resources Research 29, no. 10 (October 1993): 3561–68. http://dx.doi.org/10.1029/93wr00978.
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4
Viseur, Sophie. "Turbidite reservoir characterization : object-based stochastic simulation meandering channels." Bulletin de la Société Géologique de France 175, no. 1 (January 1, 2004): 11–20. http://dx.doi.org/10.2113/175.1.11.
Повний текст джерелаАнотація:
Abstract Stochastic imaging has become an important tool for risk assessment and has successfully been applied to oil field management. This procedure aims at generating several possible and equiprobable 3D models of subsurface structures that enhance the available data set. Among these stochastic simulation techniques, object-based approaches consist of defining and distributing objects reproducing underground geobodies. A technical challenge still remains in object-based simulation. Due to advances in deep water drilling technology, new hydrocarbon exploration has been opened along the Atlantic margins. In these turbidite oil fields, segments of meandering channels can be observed on high-resolution seismic horizons. However, no present object-based simulation technique can reproduce exactly such known segments of channel. An improved object-based approach is proposed to simulate meandering turbidite channels conditioned on well observations and such seismic data. The only approaches dealing with meandering channels are process-based as opposed to structure-imitating. They are based on the reproduction of continental river evolution through time. Unfortunately, such process-based approaches cannot be used for stochastic imaging as they are based on equations reflecting meandering river processes and not turbiditic phenomena. Moreover, they incoporate neither shape constraints (such as channel dimensions and sinuosity) nor location constraints, such as well data. Last, these methods generally require hydraulic parameters that are not available from oil field study. The proposed approach aims at stochastically generating meandering channels with specified geometry that can be constrained to pass through well-observations. The method relies on the definition of geometrical parameters that characterize the shape of the expected channels such as dimensions, directions and sinuosity. The meandering channel object is modelled via a flexible parametric shape. The object is defined by a polygonal center-line (called backbone) that supports several sections. Channel sinuosity and local channel profiles are controlled by the backbone and, respectively the sections. Channel generation is performed within a 2D domain, D representing the channel-belt area. The proposed approach proceeds in two main steps. The first step consists in generating a channel center-line (C) defined by an equation v=Z(u) within the domain D. The geometry of this line is simulated using a geostatistical simulation technique that allows the generation of controlled but irregular center-lines conditioned on data points. During the second step, a vector field enabling the curve (C) to be transformed into a meandering curve (C’) is estimated. This vector field acts as a transform that specifies the third degree of channel sinuosity, in other words, the meandering parts of the loops. This field is parameterized by geometrical parameters such as curvature and tangent vectors along the curve (C) and the a priori maximum amplitude of the meander loops of the curve (C’). To make channel objects pass through conditioning points, adjustment vectors are computed at these locations and are interpolated along the curves. Synthetic datasets have been built to check if a priori parameters such as tortuosity are reproduced, and if the simulations are equiprobable. From this dataset, hundred simulations have been generated and enable one to verify that these two conditions are satisfied. Equiprobability is however not always satisfied from data points that are very close and located in a multivalued part of a meander : preferential orientation of the loops may indeed be observed. Solving this issue will be the focus of future works. Nevertheless, the results presented in this paper show that the approach provides satisfying simulations in any other configurations. This approach is moreover well-suited for petroleum reservoir characterization because it only needs specification of geometrical parameters such as dimension and sinuosity that can be inferred from the channel parts seen on seismic horizons or analogues.
5
He, Fei, Qiuying Lai, Jie Ma, Geng Wei, and Weixin Li. "Numerical Simulations of Sudden Oil Spills in Typical Cross-Border Rivers in the Yangtze River Delta Region." Applied Sciences 12, no. 24 (December 19, 2022): 13029. http://dx.doi.org/10.3390/app122413029.
Повний текст джерелаАнотація:
The Taipu River is an important cross-border river in the Yangtze River Delta region and a direct channel connecting Taihu Lake and Huangpu River. Along the main stream of the Taipu River are many sources of water, such as the Wujiang, Dingzha, and Liantang Rivers. Many boats traverse these rivers transporting a wide variety of goods, including large quantities of oil, chemicals, and other dangerous goods. In the event of accidents on these vessels, spilled cargo will directly threaten the drinking water safety of people in the region. Aiming at simulating and assessing the environmental risks of sudden oil spills in rivers in the Yangtze River Delta region, this paper established a two-dimensional oil spill model of the typical transboundary Taipu River based on the MIKE21 water environment numerical simulation software developed by the Danish Institute of Water Conservancy. The established model will improve emergency response and treatment plans as well as our understanding of river oil spill progressions.
6
Magomedova, M. R., Z. A. Kurbanova, and B. A. Shangereeva. "COMPUTER SIMULATION OF DETERMINING SILTATION VOLUMES OF WATER RESERVOIR STORAGE ON THE AKSAY RIVER." Herald of Dagestan State Technical University. Technical Sciences 46, no. 4 (January 2, 2020): 102–12. http://dx.doi.org/10.21822/2073-6185-2019-46-4-102-112.
Повний текст джерелаАнотація:
Objectives. The development of a mathematical model for the increased turbidity zones of the Aksay river in order to determine the siltation volumes of the Aksay water reservoir storage.Method. The mathematical model is developed using the theory of probability and the theory of random process outliers. The model takes the normal distribution of the horizontal and vertical components of the instantaneous flow velocities into account, as well as the Rayleigh law of the distribution of their maxima. The proposed model is used to calculate the “turbidity tail” of the Aksay river.Result. Due to the multifactorial nature of the continuously associated processes of siltation and deposition of suspended and bottom sediments in the upper pounds of the Aksay reservoir storage hydrological system, a mathematical model of the reservoir accretion process is developed. This model provides the reliability of accretion forecasting with spatial and temporal correlation with the siltation process model, which is actually feasible on the basis of computer simulation.Conclusion. The developed model, which is based on a probabilistic approach and the theory of random process outliers, reflects the overall process of sediment transport in open channels. The development and execution of simulation programmes is carried out using the Microsoft Developer Studio (MDS) and the Fortran Power Station algorithmic language, which comprises not only a programming system, but also a set of tools for supporting large software projects integrated into MDS.
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NASSAR, M. A. "ONE-DIMENSIONAL HYDRODYNAMIC MODEL SIMULATING WATER STAGE IN OPEN CHANNELS (WS-1)." International Journal of Modeling, Simulation, and Scientific Computing 01, no. 02 (June 2010): 303–16. http://dx.doi.org/10.1142/s1793962310000110.
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One-dimensional (1D) numerical model was developed to simulate water stage in open channels in order to suggest solutions for practical problems in the Nile River and its branches. The continuity and momentum equations describe the unsteady flow were solved using the finite difference technique. The developed model is verified using two types of data. The first type, simulating steady flow, is a field data collected at Elbogdady reach. It is a reach located 712.80 km upstream of Roda's staff gauge on the Nile River. The second type, simulating unsteady flow, is a result of the 1D SOBEK model. It is simulating the flow field at El-Mahrousa canal. It is one of El-Kanobia canal branches at 11.47 km left side, which is fed from El-Mahmoudia canal. Simplifications were made to simulate the flow patterns around the hydraulic structures using the developed hydrodynamic model. Actually, the water levels in many branch canals under continuous flow after implementation of Irrigation Improvement Project (IIP) need to be checked. The model could be applied to estimate the water stage under different abstraction values where some reaches of the Nile River and its branch suffering. In addition, it can be used to assess the impact of water allocation. Good agreement was observed between the model results and the field observations.
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Ages, Alard, and Anne Woollard. "Tracking a Pollutant in the Lower Fraser River: A Computer Simulation." Water Quality Research Journal 23, no. 1 (February 1, 1988): 122–40. http://dx.doi.org/10.2166/wqrj.1988.010.
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Abstract A one-dimensional numerical model of the tidal portion of the Fraser estuary has been adapted to simulate the path and residence time of contaminants released in any of the lower reaches of the river. A brief discussion of the model’s original development and purpose is followed by an assessment of its accuracy in predicting currents as compared to water surface elevations. Since the flow computations in this type of model are vertically and laterally integrated, they had to be corrected to represent transport in mid-channel. These correction factors were established by several time series and spot measurements along the river, taking into account the local topography. The results were verified by tracking surface floats during three representative discharges.
9
Zhang, Weifeng G., John L. Wilkin, and Oscar M. E. Schofield. "Simulation of Water Age and Residence Time in New York Bight." Journal of Physical Oceanography 40, no. 5 (May 1, 2010): 965–82. http://dx.doi.org/10.1175/2009jpo4249.1.
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Abstract The time scales on which river inflows disperse in the coastal ocean are relevant to a host of biogeochemical and environmental processes. These time scales are examined in a modeling study of the Hudson River plume on its entry to the New York Bight (NYB). Constituent-oriented age and residence-time theory is applied to compute two time scales: mean age, which is calculated from the ratio of two model tracers, and residence time, which is calculated using the adjoint of the tracer conservation equation. Spatial and temporal variability associated with river discharge and wind is investigated. High river discharge lowers surface water age and shortens residence time in the apex of the NYB. Easterly winds increase surface water age and extend the duration waters along the Long Island coast remain in the NYB apex. Southerly winds increase age along the New Jersey coast but drive a decrease in age of offshore surface waters and prolong the time that surface waters close to the New Jersey coast stay in the NYB apex. Residence time along the Long Island coast is high in spring and summer because of the retention of water north of the Hudson shelf valley. Patterns of modeled surface water age and an age proxy computed from the ratio of satellite-measured irradiance in two channels show qualitative agreement. A least squares fit gives a statistically significant empirical relationship between the band ratio and modeled mean age for NYB waters.
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Zinoviev, A. T., A. V. Dyachenko, K. B. Koshelev, and K. V. Marusin. "Modeling of channel processes in large rivers with the use of field data." EURASIAN JOURNAL OF MATHEMATICAL AND COMPUTER APPLICATIONS 9, no. 1 (2021): 87–102. http://dx.doi.org/10.32523/2306-6172-2021-9-1-87-102.
Повний текст джерелаАнотація:
The paper deals with mathematical description of channel processes occurring in long sections of large rivers with a complex morphometry. To forecast negative manifestations of channel deformations, a computer model of river sediment transport in the study section is proposed. It is based on a three-dimensional (3D) / two-dimensional horizontal (2DH) flow model, a 2DH model of bed sediment transport and observation data. Comparative analysis of simulation results of channel processes in the Ob river section at the Barnaul water intakes and in situ data makes it possible to evaluate forecast capabilities of the designed model, in particular, for quantitative assessment of changes in channel topography of the study section caused by natural and anthropogenic impacts.
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Zinoviev, Alexander T., Alexander V. Dyachenko, Konstantin B. Koshelev, and Konstantin V. Marusin. "MODELING AND FIELD OBSERVATIONS OF CHANNEL PROCESSES OF THE SIBERIAN RIVERS. OB RIVER AT BARNAUL CITY SITE AS A CASE STUDY." Interexpo GEO-Siberia 4, no. 1 (May 21, 2021): 126–36. http://dx.doi.org/10.33764/2618-981x-2021-4-1-126-136.
Повний текст джерелаАнотація:
Computer simulation of channel morphodynamic for the section of a large river in real unsteady hydrological conditions is conducted. The Ob river channel section at Barnaul city is investigated. At the site considered the channel processes cause serious hazard to some important structures such as the municipal water intake and the power line. The time of modeling covers the period from the flood peak to the low water stage. The simulation is implemented by means of Delft3D program suite. The sediment transport is calculated by two types of Van Rijn’s formula (1984 and 1993). The simulation results are verified by the field data collected at the study site over the same time period. These results show poor agreement with the field data. The river bed erosion spatial pattern modeled differs from the real one significantly. Probably a reason of this discrepancy is that the formula used can’t estimate the sediment transport value correctly.
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Zhang, Yuxuan, Ranhang Zhao, Haofang Wang, Tao Peng, and Huaqing Zhao. "A Gateway to Rapid Prediction of Water Quality: A Case Study in China’s South-to-North Water Diversion Project." Water 13, no. 17 (September 1, 2021): 2407. http://dx.doi.org/10.3390/w13172407.
Повний текст джерелаАнотація:
Water quality assurance is the primary factor for the successful operation of water diversion projects across river basins. The rapid prediction of water pollution is the basis for timely and effective emergency control and disposal measures. In China, since the open channels intersect with numerous waterways and traffic arteries, water transfer projects are prone to sudden water pollution accidents. In this paper, the rapid prediction method was developed for sudden water pollution accidents that possibly occurred in the East Route of the South-to-North Water Diversion Project (ERP) in Shandong Province. With the empirical formula of the pollution transfer law, a rapid prediction model of water quality (WQRP) was established based on the simulation of the typical accidents in the main channel. Finally, four typical accidents were selected as application examples, and the prediction results were compared with the results from a computer numerical simulation to demonstrate the validity of the model. The results showed that the prediction results by the WQRP model meet the accuracy requirements. This method is of great significance for providing water transport security in the extreme conditions of long-distance water transfer projects.
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Pham Van, Chien, Benjamin De Brye, Anouk De Brauwere, A. J. F. (Ton) Hoitink, Sandra Soares-Frazao, and Eric Deleersnijder. "Numerical Simulation of Water Renewal Timescales in the Mahakam Delta, Indonesia." Water 12, no. 4 (April 2, 2020): 1017. http://dx.doi.org/10.3390/w12041017.
Повний текст джерелаАнотація:
Water renewal timescales, namely age, residence time, and exposure time, which are defined in accordance with the Constituent-oriented Age and Residence time Theory (CART), are computed by means of the unstructured-mesh, finite element model Second-generation Louvain-la-Neuve Ice-ocean Model (SLIM) in the Mahakam Delta (Borneo Island, Indonesia). Two renewing water types, i.e., water from the upstream boundary of the delta and water from both the upstream and the downstream boundaries, are considered, and their age is calculated as the time elapsed since entering the delta. The residence time of the water originally in the domain (i.e., the time needed to hit an open boundary for the first time) and the exposure time (i.e., the total time spent in the domain of interest) are then computed. Simulations are performed for both low and high flow conditions, revealing that (i) age, residence time, and exposure time are clearly related to the river volumetric flow rate, and (ii) those timescales are of the order of one spring-neap tidal cycle. In the main deltaic channels, the variation of the diagnostic timescales caused by the tide is about 35% of their averaged value. The age of renewing water from the upstream boundary of the delta monotonically increases from the river mouth to the delta front, while the age of renewing water from both the upstream and the downstream boundaries monotonically increases from the river mouth and the delta front to the middle delta. Variations of the residence and the exposure times coincide with the changes of the flow velocity, and these timescales are more sensitive to the change of flow dynamics than the age. The return coefficient, which measures the propensity of water to re-enter the domain of interest after leaving it for the first time, is of about 0.3 in the middle region of the delta.
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Qi, Lan, Hui Chen, Xiao Wang, Wencai Fei, and Donghai Liu. "Establishment and application of three-dimensional realistic river terrain in the numerical modeling of flow over spillways." Water Supply 18, no. 1 (May 31, 2017): 119–29. http://dx.doi.org/10.2166/ws.2017.101.
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Abstract We present an integrated three-dimensional (3D) spillway model where the realistic and complicated river terrain is implemented by the platform CATIA (Computer Aided Three Dimensional Interactive Application). This integrated 3D spillway model allows for complicated topographic and geomorphic conditions and describes the spatial distribution of the spillway dam (upstream reservoir, downstream river channel and the spillway dam itself) precisely, thus making it a real alternative to the physical model. Furthermore, this model provides the premise and possibility of a full-scale simulation of the spillway flow, that is, it can not only be used to study the hydraulics on the spillway face, but also can be used to study the hydraulics along the downstream river channel and estimate the scour problem associated with both the spillway flow and downstream river channel. In this model, turbulence was simulated using RNG k−ɛ equations. The flow velocity and surface pressure from the numerical model were verified by the data from experiments. Moreover, the river flow was studied and flow velocities downstream were obtained. The scour formed downstream of a ski-jump was also studied in this study on the location and shape of a scour hole. In all, this study provides new approaches for solving relevant hydraulic engineering problems.
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Zhang, Min, and Rui Xun Lai. "The Water Transferred of Meandering River in Cellular Model." Advanced Materials Research 452-453 (January 2012): 842–45. http://dx.doi.org/10.4028/www.scientific.net/amr.452-453.842.
Повний текст джерелаАнотація:
We have known that many of the main features of river can be captured in a relatively simple cellular computer model. Here we examine some of the detailed characteristics of this model. We show a new tangential angle and special treatment method in curvature channel in a simple cellular model. The water distribute will be determined by the tangential angle which represent the flow direction. And the same tangential angle cellular in curvature reach will be transport in one group in filially. The results show it can make the flow routing conformed to the real river, and solve the question of curve bending coefficient is too large. The results of the routing scheme are compared with field measurements of cross-section, with the predictions of a more close to the real. It’s indicate that the curvature flow routing scheme outlined here is able to overcome some of the limitations of previous simple cellular automata models and may be suitable for use in curvature reach of river modeling water and sediment transport and channel change in complex fluvial environments. As such this research represents a small and ongoing contribution to the field of numerical simulation of curvature channel processes.
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Li, Jiazheng, and Yiqing Lv. "Risk Assessment of Debris Flow in Huyugou River Basin Based on Machine Learning and Mass Flow." Mobile Information Systems 2022 (August 24, 2022): 1–10. http://dx.doi.org/10.1155/2022/9751504.
Повний текст джерелаАнотація:
The Huyugou river basin is a typical debris flow river basin in the Shanxi Province, which has great harm after the outbreak and seriously affects the safety of people’s lives and property. Therefore, it is urgent to carry out debris flow risk assessment. In this paper, a machine learning algorithm is implemented to assess the disaster susceptibility of each branch gully in a river basin of the Huyugou. Furthermore, its high-susceptibility branch gully and main gully were selected as the starting points of debris flow simulation for numerical simulation. The machine learning algorithm is implemented in a cloud-edge platform to minimize the model training and prediction times. Under the simulated rainfall conditions of major debris flow disasters, e.g., the one that occurred in 1996, the accuracy rate reached 84%. The results show that the debris flow susceptibility of each branch gully in the study area is mainly affected by the peak flow rate of the river basin, the length of the main gully, and the relative height difference of the river basin. The total risk area of debris flow is 1.91 × 105 m2, and the high-risk area accounts for 52.18% of the total area. It is mainly located in the upper part of the main gully accumulation area and the confluence of each channel and the main gully. The middle-risk area accounts for 36.14% of the total area, and the low-risk area accounts for less. We also observed significant reduction, from 34.68% to 36.98%, in the training and prediction times of the machine learning models when implemented over the proposed edge-cloud framework. The reappearance of debris flow in the study area is relatively accurate, which provides a certain scientific basis for the risk assessment of debris flow in the future.
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Maatooq, Jaafar S., and Luay K. Hameed. "2D Model to Investigate the Morphological and Hydraulic Changes of Meanders." Engineering and Technology Journal 38, no. 1A (January 25, 2020): 9–19. http://dx.doi.org/10.30684/etj.v38i1a.95.
Повний текст джерелаАнотація:
River engineering investigations require some level of hydrodynamic and morphologic analysis. The detailed of the hydraulic and morphologic features through meander evolution can be recorded by the numerical model spatially and temporally. The Center for Computational Hydro-science and Engineering, two- dimensional model (CCHE2D V3.29) was adopted to investigate the hydraulic and morphologic changes through meander’s evolution. Through the experimental work, a series of experiments runs were carried out through combining different geometric and hydraulic parameters to produce different experiment conditions. These parameters are flow rate, bed slope, and different initial incised and wide channels for both rectangular and trapezoidal sections. The CCHE2D model was calibrated and verified using two sets of experimental data. According to the computed values of statistical indicators, BIAS, NSE, and MAE of 0.0084, 0.96, and 0.0132 respectively for water level simulation, and 0.007,0.94, and 0.0182 respectively for bed level simulation, the calibrated Manning’s roughness which gives an acceptable agreement between simulated and measured water and bed levels was 0.029. The verification results were evaluated by the same statistical indicators of BIAS, NSE, and MAE of 0.09, 0.81, and 0.018, respectively, as evidenced by the statistical indicators, values that the CCHE2D model was reasonably capable of simulating the hydraulic and morphological changes through meander evolution.
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Payne, J. A., G. D. Moys, C. J. Hutchings, and R. J. Henderson. "Development, Calibration and Further Data Requirements of the Sewer Flow Quality Model Mosqito." Water Science and Technology 22, no. 10-11 (October 1, 1990): 103–9. http://dx.doi.org/10.2166/wst.1990.0294.
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MOSQITO is the initial version of a sever flow quality model being developed by Hydraulics Research Ltd and the Water Research Centre as part of the UK River Basin Management programme. MOSQITO I simulates the time-varying behaviour of suspended solids, biochemical oxygen demand, chemical oxygen demand, ammoniacal nitrogen and hydrogen sulphide on catchment surfaces and in sewer systems. The model produces discharge pollutographs for these determinands which can be used as input to a river water quality model. MOSQITO consists of four sub-models which represent washoff from catchment surfaces, foul water inflow, pollutant behaviour in pipes and channels, and pollutant behaviour in ancillary structures within drainage systems. These sub-models are linked to the flow simulation model incorporated in the WALLRUS package which is the latest computer implementation of the Wallingford Procedure. The rationale behind the model, its structure and its operational basis have been discussed elsewhere (Moys and Henderson, 1988) and are therefore described briefly so that emphasis can be placed on the aspects which follow. Calibration and verification of the model are being carried out using data from a variety of experimental catchments in the UK. These catchments have been selected to exhibit a wide range of characteristics and include separate and combined sewer systems. Results of the calibration work are presented together with illustrations of the performance of the various sub-models and the overall model.
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Głogowski, Arkadiusz, and Mieczysław Chalfen. "Analysis of the effectiveness of the systems protecting against the impact of water damming in the river on the increase of groundwater level on the example of the Malczyce dam." ITM Web of Conferences 23 (2018): 00011. http://dx.doi.org/10.1051/itmconf/20182300011.
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The aim of the article is to determine to what extent individual elements of the project protecting the village of Rzeczyca and adjacent areas against flooding after the planned damming up of water in the Odra on the Malczyce dam. The assessment of the impact of damming on the nearby towns was made using a mathematical model based on a two-dimensional and non-stationary version of the Boussinesq equation and the finite element method (FEM). In the simulations, the proprietary FIZ software was used for calculating water flow and chemical pollution in a porous medium. Four computer simulations were carried out, modelling the flow of groundwater in the left-bank Odra valley. The first simulation was run in pre-towering conditions, the second one included water damming without additional safeguards, the third one with a watertight membrane and the fourth one with a membrane and a drainage channel.
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Balogun, OS, and HO Ganiyu. "STUDY AND ANALYSIS OF ASA RIVER HYPOTHETICAL DAM BREAK USING HEC-RAS." Nigerian Journal of Technology 36, no. 1 (December 29, 2016): 315–21. http://dx.doi.org/10.4314/njt.v36i1.39.
Повний текст джерелаАнотація:
Impounded reservoirs provide beneficial functions such as flood control, recreation, hydropower and water supply but they also carry potential risks. Spontaneous dam break phenomenon can occur and the resultant flooding may cause substantial loss of life and property damage downstream of the dam. A hypothetical dam break on Asa Dam located in Ilorin, Kwara State, Nigeria was analyzed using United States Army Corps of Engineers (USACE), Hydrologic Engineering Center’s River Analysis System (HEC-RAS) computer model. Unsteady flow simulation was performed using geometric data obtained from Digital Terrain Model (DTM) with 100-year, 24 hr flow event. The HEC-RAS was used in concert with HEC-GeoRAS to assess the flood hazard along the Asa River channel starting from the dam axis and approximately 12 km towards the downstream as a result of the dam break. The highest discharge Q (1913.66 m3/s) and the highest peak stage (277.35 m) just below the dam were produced with breach width of 130.86 m and time of failure of 1.45 hours. The outcome of the analysis showed that in the event of such failure of Asa dam, some areas which include industrial and residential sections along the river channel are at very high risk of being inundated due to the significant difference in the value of the produced water surface elevation and existing ground elevation affecting thousands of people living along the channel immediate vicinity. http://dx.doi.org/10.4314/njt.v36i1.39
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Ehsani, Farshad, Seyed Ghorban Hosseini, and Hossein Soury. "Modeling of Unsteady Flow through the Canals by Semiexact Method." Modelling and Simulation in Engineering 2014 (2014): 1–12. http://dx.doi.org/10.1155/2014/495715.
Повний текст джерелаАнотація:
The study of free-surface and pressurized water flows in channels has many interesting application, one of the most important being the modeling of the phenomena in the area of natural water systems (rivers, estuaries) as well as in that of man-made systems (canals, pipes). For the development of major river engineering projects, such as flood prevention and flood control, there is an essential need to have an instrument that be able to model and predict the consequences of any possible phenomenon on the environment and in particular the new hydraulic characteristics of the system. The basic equations expressing hydraulic principles were formulated in the 19th century by Barre de Saint Venant and Valentin Joseph Boussinesq. The original hydraulic model of the Saint Venant equations is written in the form of a system of two partial differential equations and it is derived under the assumption that the flow is one-dimensional, the cross-sectional velocity is uniform, the streamline curvature is small and the pressure distribution is hydrostatic. The St. Venant equations must be solved with continuity equation at the same time. Until now no analytical solution for Saint Venant equations is presented. In this paper the Saint Venant equations and continuity equation are solved with homotopy perturbation method (HPM) and comparison by explicit forward finite difference method (FDM). For decreasing the present error between HPM and FDM, the st.venant equations and continuity equation are solved by HAM. The homotopy analysis method (HAM) contains the auxiliary parameterħthat allows us to adjust and control the convergence region of solution series. The study has highlighted the efficiency and capability of HAM in solving Saint Venant equations and modeling of unsteady flow through the rectangular canal that is the goal of this paper and other kinds of canals.
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Shih, Dong-Sin, and Gour-Tsyh Yeh. "Studying Inertia Effects in Open Channel Flow Using Saint-Venant Equations." Water 10, no. 11 (November 14, 2018): 1652. http://dx.doi.org/10.3390/w10111652.
Повний текст джерелаАнотація:
One-dimensional (1D) Saint-Venant equations, which originated from the Navier–Stokes equations, are usually applied to express the transient stream flow. The governing equation is based on the mass continuity and momentum equivalence. Its momentum equation, partially comprising the inertia, pressure, gravity, and friction-induced momentum loss terms, can be expressed as kinematic wave (KIW), diffusion wave (DIW), and fully dynamic wave (DYW) flow. In this study, the method of characteristics (MOCs) is used for solving the diagonalized Saint-Venant equations. A computer model, CAMP1DF, including KIW, DIW, and DYW approximations, is developed. Benchmark problems from MacDonald et al. (1997) are examined to study the accuracy of the CAMP1DF model. The simulations revealed that CAMP1DF can simulate almost identical results that are valid for various fluvial conditions. The proposed scheme that not only allows a large time step size but also solves half of the simultaneous algebraic equations. Simulations of accuracy and efficiency are both improved. Based on the physical relevance, the simulations clearly showed that the DYW approximation has the best performance, whereas the KIW approximation results in the largest errors. Moreover, the field non-prismatic case of the Zhuoshui River in central Taiwan is studied. The simulations indicate that the DYW approach does not ensure achievement of a better simulation result than the other two approximations. The investigated cross-sectional geometries play an important role in stream routing. Because of the consideration of the acceleration terms, the simulated hydrograph of a DYW reveals more physical characteristics, particularly regarding the raising and recession of limbs. Note that the KIW does not require assignment of a downstream boundary condition, making it more convenient for field application.
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Ortloff, Charles R. "Surveying and Hydraulic Engineering of the Pre-Columbian Chimú State: ad 900–1450." Cambridge Archaeological Journal 5, no. 1 (April 1995): 55–74. http://dx.doi.org/10.1017/s0959774300001189.
Повний текст джерелаАнотація:
The Chimú state of northern coastal Peru (ad 900–1480) developed massive irrigation-based agricultural systems supplied by intricate networks of canals drawing water from river sources in coastal valleys under their political control. Further intervalley canal systems, some up to 50 miles in length, were constructed to shunt water between river valleys to augment intravalley supplies. A high degree of civil engineering skill was necessary to construct and maintain such complex systems; knowledge of surveying and of open channel flow hydraulics was paramount. Some of the technology used by the Chimú has been investigated: surveying instruments and calculating tools have been unearthed and analyzed to provide some understanding of the technical base used for canal design. Details of the hydraulics knowledge-base have been extracted from computer simulation of the functioning of ancient Chimú canal designs. This article assembles known pieces of information related to Chimú civil engineering practice and attempts to provide a plausible methodology that could have been implemented by the Chimú to survey the precise canal bed slopes necessary for proper hydraulic functioning of large canal systems through rugged Andean foothill and mountain areas.
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Song, Jia-Ling, Jia-Wu Li, Run-Ze Xu, and Richard G. J. Flay. "Field measurements and CFD simulations of wind characteristics at the Yellow River bridge site in a converging-channel terrain." Engineering Applications of Computational Fluid Mechanics 16, no. 1 (December 26, 2021): 58–72. http://dx.doi.org/10.1080/19942060.2021.2004240.
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Zhu, Yunan, Biao Wang, Fangtong Xie, Chengxi Wu, and Peng Chao. "Data-Driven Signal Detection for Underwater Acoustic Filter Bank Multicarrier Communications." Wireless Communications and Mobile Computing 2022 (May 16, 2022): 1–9. http://dx.doi.org/10.1155/2022/4943442.
Повний текст джерелаАнотація:
By contraposing the signal detection for filter bank multicarrier (FBMC) communications with the underwater acoustic (UWA) channel, this paper analyzes the traditional imaginary interference problem and proposes a deep learning-based method. The neural network with feature extraction and automatic learning ability is employed to replace the demodulation modules to recover transmitted signals without explicit channel estimation and equalization. Sufficient data sets are generated according to the measured channel conditions in Qingjiang river, the optimization of network parameters is finished by constraining cost function in offline training, and the signal detection is carried out directly with the well-trained network in online testing. The system performance of various supervised learning models such as multilayer perceptron (MLP), convolutional neural network (CNN), and bidirectional long short-term memory (BLSTM) network is compared under different data sizes, network parameters, and prototype filters. The simulation results show that the bit error rate (BER) performance of the proposed signal detection is better than that of the classic one, which indicates that deep learning is a promising tool in UWA communication systems.
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Xie, Fangtong, Yunan Zhu, Biao Wang, Wu Wang, and Pian Jin. "End-to-End Underwater Acoustic Communication Based on Autoencoder with Dense Convolution." Electronics 12, no. 2 (January 4, 2023): 253. http://dx.doi.org/10.3390/electronics12020253.
Повний текст джерелаАнотація:
To address the problems of the high complexity and poor bit error rate (BER) performance of traditional communication systems in underwater acoustic environments, this paper incorporates the theory of deep learning into a conventional communication system and proposes data-driven underwater acoustic filter bank multicarrier (FBMC) communications based on convolutional autoencoder networks. The proposed system is globally optimized by two one-dimensional convolutional (Conv1D) modules at the transmitter and receiver, it realizes signal reconstruction through end-to-end training, it effectively avoids the inherent imaginary interference of the system, and it improves the reliability of the communication system. Furthermore, dense-block modules are constructed between Conv1D layers and are connected across layers to achieve feature reuse in the network. Simulation results show that the BER performance of the proposed method outperforms that of the conventional FBMC system with channel equalization algorithms such as least squares (LS) estimation and virtual time reversal mirrors (VTRM) under the measured channel conditions at a certain moment in the Qingjiang River.
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Ma, K., and W. L. Wei. "Simulation of Flow in a Rectangular Meandering Channel." Applied Mechanics and Materials 130-134 (October 2011): 2688–91. http://dx.doi.org/10.4028/www.scientific.net/amm.130-134.2688.
Повний текст джерелаАнотація:
This paper is concerned with the numerical solution of two-dimensional flows in a rectangular meandering channel. The technique of boundary-fitted coordinate system is used to overcome the difficulties resulting from the complicated shape of natural river boundaries; the method of physical fractional steps is used to solve the partial differential equations in the transformed plane. Comparison between computed and experimental data shows a satisfactory agreement.
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Webster, Ian T., Holger Maier, Michael Burch, and Peter Baker. "Influence of wind on water levels and lagoonriver exchange in the River Murray, Australia." Marine and Freshwater Research 48, no. 6 (1997): 541. http://dx.doi.org/10.1071/mf97027.
Повний текст джерелаАнотація:
This paper examines river water levels and water exchange between the river and an adjacent lagoon at a site on the River Murray about 150 km from its discharge point into Lake Alexandrina. Riverine water levels at the site underwent significant fluctuations (~ 0·3 m) which appeared to be mainly associated with fluctuations in the N–S component of wind rather than with discharge. The lagoon studied was connected by a channel to the river. The measured flow through the channel was almost always out and had an average rate over the 30 days of the study which was large enough to empty the lagoon in 9 days. It is hypothesized that the replenishment flow to the lagoon occurred as a seeping flow through the bank separating the lagoon from the river. Successful comparisons between measurements and computer simulations of river water level and of the flow through the channel confirmed that it was the wind stress acting on the surface that mediated variations in riverine water levels and the exchange between river and lagoon.
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Harada, Shouta, and Tadaharu Ishikawa. "Evaluation of the Effect of Hamao Detention Pond on Excess Runoff from the Abukuma River in 2019 and Simple Remodeling of the Pond to Increase Its Flood Control Function." Applied Sciences 12, no. 2 (January 12, 2022): 729. http://dx.doi.org/10.3390/app12020729.
Повний текст джерелаАнотація:
Due to the recent increase in the intensity of rainstorms, the Japanese government has announced a new policy of flexible flood mitigation measures that presupposes the release of water volumes exceeding the river channel capacity onto floodplains. However, due to the limited amount of quantitative measurement data on excess runoff, it will take time to formulate planning standards for remodeling and newly constructing flood control facilities reasonable enough under current budgetary constraints. In this study, the capacity shortage of a flood detention pond was evaluated against the excess runoff from a severe 2019 flood event by combining the fragmentary measurement data with a numerical flow simulation. Although the numerical model was a rather simple one commonly used for rough estimation of inundation areas in Japan, the results were overall consistent with the observations. Next, in accordance with the new policy, an inexpensive remodeling of the detention basin, which was designed according to conventional standards, was simulated; the upstream side of the surrounding embankment was removed so that excess water flowed up onto the floodplain gradually. Numerical experiments using the simple model indicated that the proposed remodeling increased the effectiveness of flood control remarkably, even for floods greater than the 2019 flood, without much inundation damage to upstream villages.
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Gu, Jie, Wei Chen, Xin Qin, Dan Qing Ma, Xiao Li Wang, and Ji Zhong Yang. "Simulation to Investigate the Reasons for the Sediment Deposition in the Upper Reach of the Deepwater Navigation Channel in the Changjiang River Estuary." Advanced Materials Research 610-613 (December 2012): 1237–41. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.1237.
Повний текст джерелаАнотація:
At present, the upper reach of the Deepwater Navigation Channel is silted heavily, which brings negative influences on navigation. A two-dimensional numerical model is set up to simulate the hydrodynamics of the Changjiang River Estuary with Delft3D-FLOW in this paper. This model has been validated with the observed tidal level, flow velocity magnitude and direction, and the computed results agree well with the observed data, which also shows the model can well simulate the hydrodynamics of the Changjiang River Estuary caused by the Deepwater Navigation Channel Project. Based on the analysis of computed results, especially the velocity along the South Passage and North Passage, the flood and ebb flow in the Hengsha Passage, and the flow spilt ratio of South Passage and North Passage, it presents that one fundamental reason for the sediment deposition in the upper reach of the Deepwater Navigation Channel is that the velocity along the North Passage is far less than that along South Passage, above all, the velocity in North Passage upstream of the Hengsha Passage is even smaller; another reason is that the flood and ebb flow of Hengsha Passage are large, which weakens the water exchange between the North Passage and South Channel.
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DECOENE, ASTRID, LUCA BONAVENTURA, EDIE MIGLIO, and FAUSTO SALERI. "ASYMPTOTIC DERIVATION OF THE SECTION-AVERAGED SHALLOW WATER EQUATIONS FOR NATURAL RIVER HYDRAULICS." Mathematical Models and Methods in Applied Sciences 19, no. 03 (March 2009): 387–417. http://dx.doi.org/10.1142/s0218202509003474.
Повний текст джерелаАнотація:
The section-averaged shallow water model usually applied in river and open channel hydraulics is derived by an asymptotic analysis that accounts for terms up to second order in the vertical/longitudinal length ratio, starting from the three-dimensional Reynolds-averaged Navier–Stokes equations for incompressible free surface flows. The derivation is carried out under quite general assumptions on the geometry of the channel, thus allowing for the application of the resulting equations to natural rivers with arbitrarily shaped cross sections. As a result of the derivation, a generalized friction term is obtained, that does not rely on local uniformity assumptions and that can be computed directly from three-dimensional turbulence models, without need for local uniformity assumptions. The modified equations including the novel friction term are compared to the classical Saint Venant equations in the case of steady state open channel flows, where analytic solutions are available, showing that the solutions resulting from the modified equation set are much closer to the three-dimensional solutions than those of the classical equation set. Furthermore, it is shown that the proposed formulation yields results that are very similar to those obtained with empirical friction closures widely applied in computational hydraulics. The generalized friction term derived therefore justifies a posteriori these empirical closures, while allowing to avoid the assumptions on local flow uniformity on which these closures rely.
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Yang-jun, WANG, and YIN Tai-ju. "Numerical forward Modelling of River-dominated Deltas." Applied Science and Innovative Research 4, no. 1 (January 11, 2020): p16. http://dx.doi.org/10.22158/asir.v4n1p16.
Повний текст джерелаАнотація:
A delta is a type of sedimentary system that is closely related to oil and gas. Shallow-lake delta deposits in the Mesozoic-Cenozoic strata of China are of particular interest. This delta has significant oil and gas reserves that are developed widely. Based on a numerical simulation of the sand body of the shallow-lake delta, this study analyzes the influence of various sediment conditions on the sand-body development. The formation and distribution rules of the sand body are concluded and verified, and the results can effectively guide the exploration and development of oil and gas resources. Unlike traditional flume experiments, this study adopts sediment numerical simulation technology. This approach is borrowed from the advanced achievements of computational fluid dynamics, and Delft3D is used to establish a three-dimensional numerical model of the delta. The calculation field was 20.5 km in length by 10 km in width. With the Mor-Factor set to 60, the simulation time was 45 days. The formation and the avulsion of the mouth bar, as well as the extension, migration and bifurcation of distributary channels, have been observed and studied through analysis of the simulation results. The vertical cross-section shows that the distributary channel was filled multiple times. According to distributary channel evolution characteristics combined with quantitative methods, the terminal distributary channels can be extremely developed under ideal conditions. Due to the cross-cutting and reform effort of distributary channels, sediments were spread widely and continuously. The results show that the numerical model works well in explaining the process of evolution in fluvial-dominated delta distributary channels. This study not only enables us to quantitatively understand the dynamic processes of terminal distributary channels in fluvial-dominated delta systems, but also provides a reference model for numerical simulation of hydrodynamics in sedimentology study.
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Putra, Andi Ari, Muhammad Syahid, and Andi Amijoyo Mochtar. "Calculation and Simulation of Aluminium Alloy Flange Reducer Cast Using Resin Sand Mold." EPI International Journal of Engineering 4, no. 2 (August 30, 2021): 109–14. http://dx.doi.org/10.25042/epi-ije.082021.01.
Повний текст джерелаАнотація:
One of the causes of defects in casting is due to poor gating system design. In conventional casting methods, the gating system design process is carried out by trial and error to find the best design results. Computer modeling and simulation offer process design in a much faster time, and at much less cost, compared to conventional methods. The gating system design approach with a combination of well calibrated simulation software can avoid defect before casting. Casting simulation helps to visualize the phenomena of filling, molten metal solidification, and shrinkage porosity. The resulting casting simulation can be displayed in graph variants at specific nodes with line graphs or numerical numbers manually. This study discusses the simulation of casting a flange reducer from aluminum alloy material using a resin sand mold. The initial dimensions of the gating system used are sprue of 14.5 x 8.4 x 180 mm, runner 147 x 10 x 5.5 mm, ingate 80 x 10 x 5.5 mm with a bottom gate channel system. Total of dominant porosity that occurs using the initial gating system is 65.31 % and show the undirectional solidificiation behavior. After modifying the gating system and increasing the riser size, the simulation results show directional solidification behavior starting from the thinnest part to the thickest part and ending at the riser. The shrinkage porosity can compensate with the total of porosity is 57.60 % at the riser . Modification of the channel system is required to obtain a sound casting or porosity free.
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Mah, D. Y. S., N. C. Nam, F. J. Putuhena, and P. L. Law. "Modelling of Batang Rejang for Extreme Events." Journal of Civil Engineering, Science and Technology 4, no. 3 (December 1, 2013): 1–5. http://dx.doi.org/10.33736/jcest.119.2013.
Повний текст джерелаАнотація:
Flood is a natural hazard. It happens when the water in a river channel is beyond the capacity of the channel to carry while the overflowing water is called as floodwater. Flood causes damage to life and property when it strikes a vulnerable population in the affected area. There are several townships located along Batang Rejang such as Kapit, Song, Kanowit and Sibu. The main objective of this paper is to develop a river model to map the extreme events for Batang Rejang. The method used in is river modelling by using InfoWorks RS software. This method is simulating the Batang Rejang in order to view the behaviours of the river in response to conditions and effects of extreme events over a given period of time. Flood maps computed from InfoWorks RS are for flood extent analysis as it provides insights to the damage for different locations at different flows. The maps are also useful for related authorities or parties to locate human activities at the catchment area and to carry out emergency flood plans in the future.
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Guo, Dongjian, Qingcun Zeng, Jiang Zhu, and Zhuo Liu. "The dynamic structure of steady river channels." Communications in Nonlinear Science and Numerical Simulation 2, no. 2 (May 1997): 65–70. http://dx.doi.org/10.1016/s1007-5704(97)90041-1.
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Liu, Y. B., S. Gebremeskel, F. de Smedt, L. Hoffmann, and L. Pfister. "Simulation of flood reduction by natural river rehabilitation using a distributed hydrological model." Hydrology and Earth System Sciences 8, no. 6 (December 31, 2004): 1129–40. http://dx.doi.org/10.5194/hess-8-1129-2004.
Повний текст джерелаАнотація:
Abstract. The effects of river rehabilitation on flood reduction in the Steinsel sub-basin of the Alzette River basin, Grand-Duchy of Luxembourg, are discussed; the rehabilitation measures include planting and changing riparian and in-stream vegetation, and re-meandering of channelised reaches, etc. in the headwater streams. To simulate flood reduction by river rehabilitation, the streams have been classified into different orders and by assessing the response of the stream channels to the resistance or obstruction of flows. Based on this assessment, the roughness to the flow in the first and second order streams is adjusted in line with the river rehabilitation while the roughness of higher order channels downstream is unchanged. The hydrological analysis utilises the WetSpa distributed model based on spatial information on topography, soil type and land use. The increased channel roughness in the headwater channels delays the flows, so that peak discharges at the outlet of the basin are reduced. The simulation indicates that, after river naturalisation, the reduction in peak flow can be as much as 14% and the time of concentration may be delayed by as much as two hours. Also, an impact analysis has assessed the possible flood reduction for a changed climate scenario. Keywords: river rehabilitation, flood reduction, distributed hydrological modelling, WetSpa
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Nistoran, Daniela-Elena Gogoaşe, Ştefan-Mugur Simionescu, Gabriela Cîrciumaru, and Rareş-Andrei Chihaia. "Numerical simulations of flow over a side weir for diversion structures and water intakes." IOP Conference Series: Earth and Environmental Science 1136, no. 1 (January 1, 2023): 012035. http://dx.doi.org/10.1088/1755-1315/1136/1/012035.
Повний текст джерелаАнотація:
Abstract Side weirs are hydraulic structures used to divert the excess flow from a main channel into a lateral one at diversion structures or intakes, in order to control the water surface elevation or reroute part of the discharge. Flow over a side weir is considered to be a typical case of spatially varied flow, with decreasing discharge along the main channel and varying water surface elevation along the lateral crest. The objective of the paper is to apply various numerical modelling approximations (1D, 2D and 3D) using HEC-RAS and ANSYS Fluent software to virtually reproduce the flow characteristics over the side weir along the diversion canal of the Valea Iasului hydropower plant (HPP), on Argeş River (Romania). Different geometries, mesh types and sizes and the appropriate initial and boundary conditions are used for two HPP operating scenarios (fully functional and completely shut down). The water surface elevation profile along the weir crest is computed, together with a qualitative comparison between the shape of the simulated flow nappe and in-situ visualizations. Quantitative results from the numerical simulation cases are given in terms of the computed upstream and downstream weir rating curves.
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Errera, M. R., and A. Bejan. "Deterministic Tree Networks for River Drainage Basins." Fractals 06, no. 03 (September 1998): 245–61. http://dx.doi.org/10.1142/s0218348x98000298.
Повний текст джерелаАнотація:
This paper shows that the dendritic patterns formed by low-resistance channels in a river drainage basin are reproducible and can be deduced from a single principle that acts at every step in the development of the pattern: the constrained minimization of global resistance in area-to-point flow. The river basin is modeled as a two-dimensional territory with Darcy flow through a saturated heterogeneous porous medium with uniform flow addition per unit area. From one step to the next, small elements of the porous medium are dislodged and removed in ways that minimize the global flow resistance. The removed elements are replaced by channels with lower flow resistance. The channels form a dendritic pattern that is deterministic, not random. The finest details of this structure are sensitive to internal properties and external forcing, i.e. variations in the local properties of the flow medium, and the manner in which the total area-to-point flow rate varies as the structure develops. Remarkably insensitive to such effects are the basic type and rough size of the flow structure (channels versus no channels, dendrite, number of branches) and the minimized global resistance to flow.
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Hoyles, Matthew, Serdar Kuyucak, and Shin-Ho Chung. "Computer simulation of ion conductance in membrane channels." Physical Review E 58, no. 3 (September 1, 1998): 3654–61. http://dx.doi.org/10.1103/physreve.58.3654.
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Dyakonova, Tatyana, Anna Klikunova, and Alexander Khoperskov. "Hydraulic resistance due to unsteady ow in river channels: numerical simulation results." Journal of Physics: Conference Series 1400 (November 2019): 077041. http://dx.doi.org/10.1088/1742-6596/1400/7/077041.
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Booker, D. J., and M. J. Dunbar. "Application of physical habitat simulation (PHABSIM) modelling to modified urban river channels." River Research and Applications 20, no. 2 (February 12, 2004): 167–83. http://dx.doi.org/10.1002/rra.742.
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Wang, Yang Jun, Tai Ju Yin, and Zhi Hao Deng. "A Study on the Evolution of Distributary Channels in River-Dominated Deltas Using Numerical Simulations of Hydrodynamic Behaviors." Applied Mechanics and Materials 744-746 (March 2015): 1050–55. http://dx.doi.org/10.4028/www.scientific.net/amm.744-746.1050.
Повний текст джерелаАнотація:
The Fluvial-dominated delta is one of the extremely important deposition systems in oil and gas exploration. In this paper, the three-dimensional numerical simulation of hydrodynamics has been applied to the precise analysis of the formation of fluvial-dominated deltas and the evolution of their distributary channels. The model has been created using the Delft3D program, and the conditions of the numerical model have been set according to the hydrodynamic characteristics of modern rivers and deltas. The calculation field was 20.5 km in length by 10 km in width. With the Mor-Factor set to 60, the simulation time was 45 days. The formation and the avulsion of the mouth bar, as well as the extension, migration and bifurcation of distributary channels, have been observed and studied through analysis of the simulation results. The vertical cross-section shows that the distributary channel was filled multiple times. According to distributary channel evolution characteristics combined with quantitative methods, the terminal distributary channels can be extremely developed under ideal conditions. Due to the cross-cutting and reform effort of distributary channels, sediments were spread widely and continuously. The results show that the numerical model works well in explaining the process of evolution in fluvial-dominated delta distributary channels. This study not only enables us to quantitatively understand the dynamic processes of terminal distributary channels in fluvial-dominated delta systems, but also provides a reference model for numerical simulation of hydrodynamics in sedimentology study.
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Salewicz, K. A., D. P. Loucks, and C. Gandolfi. "IRIS: Interactive River Simulation program." Environmental Software 6, no. 1 (March 1991): 5–10. http://dx.doi.org/10.1016/0266-9838(91)90011-e.
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Nikora, Vladimir I., and Victor B. Sapozhnikov. "River network fractal geometry and its computer simulation." Water Resources Research 29, no. 10 (October 1993): 3569–75. http://dx.doi.org/10.1029/93wr00966.
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Mujumdar, Minal P., and Chanchal K. Mitra. "Selectivity of ionic channels: As seen through computer simulation." Computers in Biology and Medicine 21, no. 3 (January 1991): 121–30. http://dx.doi.org/10.1016/0010-4825(91)90021-z.
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Yue-jin, Wu, and Fang Da-chao. "Computer simulation of metoclopramide block of cardiac sodium channels." Journal of Tongji Medical University 12, no. 2 (June 1992): 94–97. http://dx.doi.org/10.1007/bf02887788.
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Son, Kwang Ik, Taik Jean Hwang, Man Ha Hwang, and Young Ho Yoon. "Uncertainty Improvement in a Simulation of Channel Evolution." Applied Mechanics and Materials 212-213 (October 2012): 341–44. http://dx.doi.org/10.4028/www.scientific.net/amm.212-213.341.
Повний текст джерелаАнотація:
The Four Major Rivers Restoration Project (4MRRP), one of the largest river rehabilitation projects in Korea, has being carried out during the last three years. 0.57 billion m3 of sediment was dredged to widen and deepen the channel along four major rivers, the Han, Nakdong, Geum, and Youngsan rivers. As a result of reshaping the natural channel to a trapezoidal channel, and the construction of 16 weirs, the change of longitudinal slope of the river was inevitable. The distribution of bed materials was also changed, due to dredging. Therefore, the rivers were totally disturbed, and the stability of the rivers could not be assured. In particular, the Nakdong river, the second largest river in Korea, has the characteristics of an alluvial channel. Degradation of the main channel bed caused bank erosion, and head-cut phenomena in many tributaries. Deformations of the main channels could be observed all along the river. Long-term simulation of the channel evolution and prediction of the stability of the Nakdong river have to be examined, to cope with the instability of the river, which could lead to unexpected river disasters. This study deals with the methodology of uncertainty improvement, in analysis of the simulation and confirmation with field survey data. Methodology of uncertainty improvement in description of weir, whose discharge coefficient is unknown, in a river was suggested.
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Kjerfve, B., HE Seim, AF Blumberg, and LD Wright. "Modelling of the residual circulation in Broken Bay and the lower Hawkesbury River, NSW." Marine and Freshwater Research 43, no. 6 (1992): 1339. http://dx.doi.org/10.1071/mf9921339.
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To elucidate the importance of lateral circulation in estuaries, a tidal circulation model was applied to Broken Bay and the lower Hawkesbury River estuarine system in New South Wales, Australia. The numerical simulation model solves the vertically averaged governing equations explicitly on a 61 × 51 finite difference grid, utilizing a 6.5-s computational step. The model is forced with an M2 tidal wave with a 1.1-m range, steady homogeneous wind stress, and river discharge. The time-averaged circulation is computed as residual transport velocities and consists of a series of residual circulation gyres. These gyres are due to tidal ebb-flood flow asymmetries and suggest the importance of lateral estuarine circulation. Very limited field data are consistent with this interpretation. Gyres in open areas change their sense of rotation in response to changing wind stress, whereas the gyres in the main channel appear to be independent of wind stress. With river discharge increased from 38 to 1250 m3 s-1, the gyres are replaced by strong ocean-directed residual velocities. The residual Stokes' drift is everywhere landward-directed and is weak except in shallow, constricted areas.
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WEI, Ming-dong, Yun-feng ZHANG, Ye-rong ZHANG, and Zi-yi PAN. "Modeling and simulation of pinhole channels." Journal of China Universities of Posts and Telecommunications 17, no. 2 (April 2010): 67–71. http://dx.doi.org/10.1016/s1005-8885(09)60449-0.
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Wang, Pingyi, Jian Li, Meili Wang, Jielong Hu, and Fan Zhang. "Numerical Simulation of the Hydraulic Characteristics and Fish Habitat of a Natural Continuous Meandering River." Sustainability 14, no. 16 (August 9, 2022): 9798. http://dx.doi.org/10.3390/su14169798.
Повний текст джерелаАнотація:
Increasing international attention is being focused on the construction of ecological waterways. Ecological waterways are not only able to successfully sustain the navigational functions for ships, but also provide a stable long-term environment in which fish can survive. In nature, meandering rivers are the most common form. Compared with straight rivers, their flow conditions are complex and not conducive to ship navigation and fish survival. There has been less research conducted on the construction of ecological waterways in naturally curving rivers. Therefore, in this paper, a naturally continuous curved river was used as a research object, and numerical simulation was employed to study the hydraulic characteristics of the river and the survival environment by fish by introducing the Shannon diversity index. It was concluded that a naturally continuous curved river cannot meet the navigational requirements and does not provide a stable survival environment for fish. After proposing a targeted channel restoration plan, the hydraulic characteristics of the flow were significantly improved, and the flow velocity Shannon diversity index was reduced. The restored channel met the navigational requirements of vessels, and provided a more stable environment for fish. In the construction of the continuous bend river ecological corridor, the location of the continuous bend stream connection was used as a key restoration area. This paper provides ideas and basic research for the sustainable development of ecological river channels and the construction of continuous curved river channels.