Journal articles on the topic 'River engineering Computer simulation'
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1
ShahiriParsa, Ahmad, Mohammad Noori, Mohammad Heydari, and Mahmood Rashidi. "Floodplain Zoning Simulation by Using HEC-RAS and CCHE2D Models in the Sungai Maka River." Air, Soil and Water Research 9 (January 2016): ASWR.S36089. http://dx.doi.org/10.4137/aswr.s36089.
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River flooding causes several human and financial casualties. It is necessary to perform research studies and implement subsequent actions consistent with the nature of the river. In order to reduce flood damage, floodplain zoning maps and river cross-sectional boundaries are important to nonstructural measures in planning and optimizing utilization of the areas around the river. Due to the complex behavior of the rivers during floods, computer modeling is the most efficient tool with the least possible cost to study and simulate the behavior of the rivers. In this study, one-dimensional model Hydrologic Engineering Centers–-River Analysis System and two-dimensional model CCHE2D were used to simulate the flood zoning in the Sungai Maka district in Kelantan state, Malaysia. The results of these two models in most sections approximately match. Most differences in the results were in the shape of the river.
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Sekine, M., M. Ukita, and H. Nakanishi. "Systematic Pollutegraph Simulation for Real Scale River Basin." Water Science and Technology 23, no. 1-3 (January 1, 1991): 141–50. http://dx.doi.org/10.2166/wst.1991.0410.
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This study describes the model for predicting the run-off load of pollutants through rivers into eutrophic lakes and inner sea areas. The model is composed of three stages: discharged load prediction; flow-rate prediction; and run-off load prediction. The discharged load in the river basin is estimated by using a pollutant loading factor method. The flow-rate which is necessary for the formula to predict the run-off load, was obtained by a tank model method. The run-off load prediction process consists of two stages: flow-out stage and flow-down stage. The flow-out stage represents the process in which the discharged load, including that from non-point source, flows out through gutters or small streams into the main river. The flow-down stage represents the process in which the flow-out load flows down through the main river to an observing station. There have been many studies dealing with water quality and load of pollutants in rivers. However, only a few of these studies have analyzed the relationship of human activities in the river basins quantitatively. Using this model, a computer program for pollutegraph simulation was constructed and applied to the river Ibo in Hyougo prefecture, JAPAN. The results obtained showed in accordance with the data obtained from field investigation.
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Chen, Sun. "Water Pollution Simulation over a River Basin Using a Computer Graphic Model." Water Science and Technology 24, no. 6 (September 1, 1991): 101–8. http://dx.doi.org/10.2166/wst.1991.0145.
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A Computer Graphic Model (CGM) was realized on a personal computer for the purpose of river water pollution simulation and planning. With the aid of common software AutoCAD, a color map of a complex river system was established and a suite of graphic symbol blocks such as pollution source, water intake, wastewater treatment plant etc. was designed to fit the needs of basin pollution management and planning. A person can insert, move/remove or modify these symbol blocks in the CGM of the river basin freely. While a new idea is confirmed, a simulation program POLSIM (written with AutoLISP) can be started which redraws the river with different width and color by the mean flow quantity and water quality. The result of a case study and a group of photographs is presented. The methodology of CGM makes the planning process of basin water pollution control easier, visual and interactive. CGM is a friendly tool to link the decision maker, planner and system analyst with active graphics.
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Suzuki, M., K. Chihara, M. Okada, H. Kawashima, and S. Hoshino. "Development of Dialog System Model for Eutrophication Control between Discharging River Basin and Receiving Water Body – Case Study of Lake Sagami (Japan)." Water Science and Technology 21, no. 12 (December 1, 1989): 1821–24. http://dx.doi.org/10.2166/wst.1989.0178.
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A computer program based on expert system software was developed and proposed as a prototype model for water management to control eutrophication problems in receiving water bodies (Suzuki etal., 1988). The system has several expert functions: 1. data input and estimation of pollution load generated and discharged in the river watershed; 2. estimation of pollution load run-off entering rivers; 3. estimation of water quality of receiving water bodies, such as lakes; and 4. assisting man-machine dialog operation. The program can be used with MS-DOS BASIC and assembler in a 16 bit personal computer. Five spread sheets are utilized in calculation and summation of the pollutant load, using multi-windows. Partial differential equations for an ecological model for simulation of self-purification in shallow rivers and simulation of seasonal variations of water quality in a lake were converted to computer programs and included in the expert system. The simulated results of water quality are shown on the monitor graphically. In this study, the expert system thus developed was used to estimate the present state of one typical polluted river basin. The river was the Katsura, which flows into Lake Sagami, a lake dammed for water supply. Data which had been actually measured were compared with the simulated water quality data, and good agreement was found. This type of expert system is expected to be useful for water management of a closed water body.
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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.
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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.
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Awang Ali, Awang Nasrizal, and Junaidah Ariffin. "Model Reliability Assessment: A Hydrodynamic Modeling Approach for Flood Simulation in Damansara Catchment Using InfoWorks RS." Advanced Materials Research 250-253 (May 2011): 3769–75. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.3769.
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This paper presents the flood inundation model using a hydrodynamic approach for flood simulation. A Digital Elevation Model (DEM) for Damansara Catchment was developed and integrated into the InfoWorks River Simulation (RS) program. Hydrographic surveying activity was carried out to collect existing Damansara River cross-section. The 3D flood model was calibrated using the 26th February 2006 and 15th October 2008 flooding event data. The model was validated using the flooding event on 21st March 2007. This computer simulation results produced hydrograph that indicates the capability of the model in dealing with regional flood analysis for future usage in designing structural flood measures.
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Ilich, Nesa. "Improvement of the return flow allocation in the Water Resources Management Model of Alberta Environment." Canadian Journal of Civil Engineering 20, no. 4 (August 1, 1993): 613–21. http://dx.doi.org/10.1139/l93-078.
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This paper describes recent developments related to a new return flow algorithm built into the Water Resources Management Model (WRMM) of Alberta Environmental Protection. An earlier return flow allocation method which was used in the WRMM did not always give satisfactory results. It was essential to fix this problem, since correct modelling of the return flows in overall river basin management is of crucial importance. The new return flow algorithm offers more reliable return flow allocation without detrimental effects on the overall model solution. This model is a major river basin planning tool in western Canada used to analyze responses of a river basin to varying operating policies or structural developments. It is a simulation model with a nested optimization subprogram. As a deterministic, steady state, and surface water allocation model, it normally relies on the estimates of natural flows and water demands throughout the river basin. The WRMM can provide quick simulations of any river basin with any number of components within a microcomputer environment. The model is used in ongoing river basin management studies in Alberta and other western provinces in Canada. Key words: water management, computer modelling, simulation, optimization, irrigation.
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Li, Shuanhu, Jun Yang, and Ziwen Zhang. "Research on 3D International River Visualization Simulation Based on Human-Computer Interaction." Wireless Communications and Mobile Computing 2020 (December 1, 2020): 1–12. http://dx.doi.org/10.1155/2020/8838617.
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With the development of digitalization in various fields, the water conservancy field is gradually developing digital three-dimensional visualization research to promote the development of digital watershed construction. This paper deeply analyzes and discusses the theory and application of three-dimensional visualization of river water scenes and realizes an interactive visual simulation system based on virtual reality technology, which simulates simulation and operation management, which can greatly accelerate the data. The processing speed makes the huge data be effectively utilized to provide visual interaction means for numerical simulation and data analysis, improve the efficiency of numerical calculation, and realize human-computer interaction communication, so that people can observe the phenomena and laws that are difficult to observe by traditional methods. The rationality of the mathematical model is analyzed for effectiveness.
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Vichiantong, Sutatip, Thida Pongsanguansin, and Montri Maleewong. "Flood Simulation by a Well-Balanced Finite Volume Method in Tapi River Basin, Thailand, 2017." Modelling and Simulation in Engineering 2019 (January 15, 2019): 1–13. http://dx.doi.org/10.1155/2019/7053131.
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Flood simulation of a region in southern Thailand during January 2017 is presented in this work. The study area covers the Tapi river, the longest river in southern Thailand. The simulation is performed by applying the two-dimensional shallow water model in the presence of strong source terms to the local bottom topography. The model is solved numerically by our finite volume method with well-balanced property and linear reconstruction technique. This technique is accurate and efficient at solving for complex flows in the wet/dry interface problem. Measurements of flows are collected from two gauging stations in the area. The initial conditions are prepared to match the simulated flow to the measurements recorded at the gauging stations. The accuracy of the numerical simulations is demonstrated by comparing the simulated flood area to satellite images from the same period. The results are in good agreement, indicating the suitability of the shallow water model and the presented numerical method for simulating floodplain inundation.
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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.
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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.
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Scaratos, P. D. "Computer modeling of fecal coliform contamination of an urban estuarine system." Water Science and Technology 44, no. 7 (October 1, 2001): 9–16. http://dx.doi.org/10.2166/wst.2001.0378.
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This study is focused on the investigation of the sources, distribution and fate of fecal coliform populations in the North Fork of the New River that flows through the City of Fort Lauderdale, Florida, USA. The dynamics of this brackish river are driven by weak tides, regulated freshwater discharges, overland runoff, storm water drainage from sewers, and groundwater exchange. Extensive field studies failed to document any alleged source(s) of contamination, including birds, domesticated and undomesticated mammals, humans, septic tank leakage, urban runoff, non-point discharges from agricultural lands, waste disposal from live-aboard vessels and/or in situ re-growth of fecal coliform. In order to facilitate field sampling, and support the data analyses efforts, computer simulations were applied to assess the likelihood of the various possible pollution scenarios. The physically based computer model used is the WASP (Water Quality Analysis Simulation Program Modeling System) of the US Environmental Protection Agency. In addition, the Neural Network MATLAB Toolbox was utilized for data analysis. WASP was able to accurately simulate the water hydrodynamics and coliform concentrations within the North Fork, while the neural network assisted in identifying correlations between fecal coliform and the various parameters involved. The numerical results supported the conclusion that fecal coliform were introduced by the animal populations along the riverbanks and by storm water washout of the adjacent drainage basins and the banks. The problem is exaggerated due to the low flashing capacity of the river.
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Song, Zida, Quan Liu, Zhigen Hu, Chunsheng Zhang, Jinming Ren, Zhexin Wang, and Jianhai Tian. "Construction Diversion Risk Assessment for Hydropower Development on Sediment-Rich Rivers." Energies 13, no. 4 (February 19, 2020): 938. http://dx.doi.org/10.3390/en13040938.
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Hydropower is an important renewable energy, and Construction Diversion Risk (CDR) should be highlighted and assessed during hydropower development. Since sediment-rich rivers are widely existing around the world and have great hydro-energy potential, assessing CDR for hydropower development on sediment-rich rivers in terms of engineering feasibility is of significance. This paper proposes a CDR assessment method for the sediment-rich hydropower development environment. The method is concise and practical, reflects diversion uncertainties and correlation, and mainly adopts the Gumbel–Hougaard Copula and the Monte Carlo Simulation. Through simulating flood evolution and sediment impact during diversion, the method can assess CDR basing on the cofferdam overtopping probability. Case results show that the proposed method can achieve CDR assessment on a sediment-rich river and highlights sediment impact on the diversion risk. Through results discussion, the risk feature of construction diversion on sediment-rich rivers is revealed, that sediment impact causes the dynamic and yearly-risen CDR. Hence, our conclusions are: (1) the proposed method is feasible, effective and has industrial potential, and (2) a diversion scheme on sediment-rich rivers is suggested that adopts the design with high or yearly-heightening cofferdams, based on the advanced CDR assessment to cope with the risk features of sediment-rich diversion environments.
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Liang, Shin-Jye, and Frank Molkenthin. "A virtual GIS-based hydrodynamic model system for Tamshui River." Journal of Hydroinformatics 3, no. 4 (October 1, 2001): 195–202. http://dx.doi.org/10.2166/hydro.2001.0018.
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A computer infrastructure which integrates the geographic information system (GIS), hydrodynamic model, visualization and network applications was developed and applied in Tamshui River, Taiwan. A digital terrain model (DTM) of the study area was first generated. We used it as a basis to construct the computation grids, conduct the flow simulations, and visualize the predicted flow scenarios in the virtual world. The three-dimensional hydrodynamic and water quality model system WQMAP was employed to simulate flows under the tidal forcing, upstream river inflows and seawater–freshwater interactions of Tamshui River. Model predictions were generally in good agreement with other simulations. Computed results were visualized in both the innovative virtual reality (VR) environment and Internet-based collaborative visualization environment (CVE). The VR environment enabled us to observe firsthand the complicated flow phenomena in the virtual world. Internet-based CVE supports distributed visualization and collaboration. The GIS-based system exhibits great potential in data visualization capabilities and the improvement of water management. We anticipate that these computer technologies will popularly be applied to hydroinformatics and other related domains in the foreseeable future.
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Mohamed, M., J. D. Stednick, and F. M. Smith. "Comparison of field measurements to predicted reaeration coefficients, k2, in the application of a water quality model, QUAL2E, to a tropical river." Water Science and Technology 46, no. 9 (November 1, 2002): 47–54. http://dx.doi.org/10.2166/wst.2002.0202.
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Some of the many tools used for watershed management are mathematical and computer models for wasteload allocations. QUAL2E is one of the most popular water quality models used for such purposes. The question arises as to whether the model is applicable in a different climate such as that in the tropics. In this study, QUAL2E was used to model Sg. Selangor River in Malaysia using the predictive equations for reaeration coefficient (k2) within the model and the measured reaeration coefficients for the river. The study results indicated that use of the reaeration coefficient (k2) measured at Sg. Selangor River did give the lowest standard error (SE) for the simulation of water quality during the 7Q10 low-flow period which is considered as the worst scene scenario in water quality modeling. But during calibration and validation using actual low-flow discharge data, the measured reaeration coefficients did not give the lowest standard error (SE). In conclusion, the results indicated that QUAL2E is applicable in tropical rivers when used with the modeled river parameters (i.e. hydraulic parameters, meteorological conditions etc.). Measured reaeration coefficients produced good results and several predictive equations also produced comparatively good results.
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Peng, Jiayu, Chunling Jin, Yue Wu, Zeying Hou, Sijia Gao, Zhaosheng Chu, and Binghui Zheng. "Modeling Non-Point Source Nutrient Loads with Different Cropping Systems in an Agricultural Lake Watershed in Southwestern China: From Field to Watershed Scale." Mathematics 10, no. 21 (October 31, 2022): 4047. http://dx.doi.org/10.3390/math10214047.
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Understanding the influence of cropping systems on non-point source pollution (NPSP) is crucial, since NPSP has become the major nutrient source of lake eutrophication. How to identify the characteristics of the N and P balance at different spatial and temporal scales remains a challenge in pollution control and decision-making. In this study, we built a soil and water assessment tool (SWAT) model coupled with an export coefficient model for a NPSP simulation in the North of Erhai Lake Basin (NELB). A method was proposed to study the N and P transport from fields and the individual sub-basins to Erhai Lake using SWAT simulation. The results showed that the N and P loss fields were mainly situated in the vicinity of the Fengyu river and along the mainstream of the Miju and Mici rivers. N and P loss fields were mainly occupied by rice–broad bean/rice–rapeseed crops and vegetables. While the critical N and P load contribution areas were situated in the vicinity of downstream of the Miju, Yong’an, and Luoshi rivers. The effects of different cropping systems on the N and P export to the watershed were insignificant in the NELB and decreased by 4–9% when changing cropping system compared to the original crops. The NPSP discharged from the critical areas was retained and purified by the flow and the reservoirs scattered along the rivers, and it was noticed that the N and P loss was mainly from the critical pollution discharge areas located downstream of Miju river. This study can provide an important simulation method for understanding NPSPs and, therefore, can help authorities improve agricultural land use and reduce lake pollution.
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Abourraja, Mohamed Nezar, Mustapha Oudani, Mohamed Yassine Samiri, Jaouad Boukachour, Abdelaziz Elfazziki, Abdelhadi Bouain, and Mehdi Najib. "An improving agent-based engineering strategy for minimizing unproductive situations of cranes in a rail–rail transshipment yard." SIMULATION 94, no. 8 (October 6, 2017): 681–705. http://dx.doi.org/10.1177/0037549717733050.
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Nowadays, seaports seek to achieve a better massification (massive transportation of containers) share of their hinterland transport by promoting rail and river connections in order to more rapidly evacuate increasing container traffic shipped by sea and to avoid landside congestion. The attractiveness of a seaport to shipping enterprises depends not only on its reliability and nautical qualities but also on its massified hinterland connection capacity. Contrary to what has been observed in Europe, the massification share of Le Havre seaport has stagnated in recent years. To overcome this situation, Le Havre Port Authority is putting into service a multimodal hub terminal linked only with massified modes. In this study, we focus on rail–rail transshipment of this new terminal, specifically on minimizing unproductive situations of cranes to improve crane productivity and to speed up freight train processing. To this end, an improving agent-based engineering strategy called the “crane anti-collision strategy” is proposed and tested using multi-method simulation software (Anylogic). In a numerical study, the simulation results reveal that our developed model is very satisfactory and outperforms other existing simulation models.
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Pindjaková, Tatiana, Stanislav Kelčík, and Andrej Šoltész. "Simulation of flood progress on the River Gidra." Pollack Periodica 11, no. 1 (April 2016): 25–34. http://dx.doi.org/10.1556/606.2016.11.1.3.
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Lee, C.-S., and F.-B. Hsiao. "Implementation of vision-based automatic guidance system on a fixed-wing unmanned aerial vehicle." Aeronautical Journal 116, no. 1183 (September 2012): 895–914. http://dx.doi.org/10.1017/s000192400000734x.
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Abstract This paper presents the design and implementation of a vision-based automatic guidance system on a fixed-wing unmanned aerial vehicle (UAV). The system utilises a low-cost ordinary video camera and simple but efficient image processing techniques widely used in computer-vision technology. The paper focuses on the identification and extraction of geographical tracks such as rivers, coastlines, and roads from real-time aerial images. The image processing algorithm primarily uses colour properties to isolate the geographical track of interest from its background. Hough transform is eventually used to curve-fit the profile of the track which yields a reference line on the image plane. A guidance algorithm is then derived based on this information. In order to test the vision-based automatic guidance system in the laboratory without actually flying the UAV, a hardware-in-the-loop simulation system is developed. Description regarding the system and significant simulation result are presented in the paper. Finally, an actual test flight where the UAV successfully follows a stretch of a river under automatic vision-based guidance is also presented and discussed.
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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.
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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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Huan, Yue, Yubin Tian, and Dianpeng Wang. "A Weighted Surrogate Model for Spatio-Temporal Dynamics with Multiple Time Spans: Applications for the Pollutant Concentration of the Bai River." Mathematics 10, no. 19 (October 1, 2022): 3585. http://dx.doi.org/10.3390/math10193585.
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Simulations are often used to investigate the flow structures and system dynamics of complex natural phenomena and systems, which are significantly harder to obtain from experiments or theoretical analyses. Surrogate models are employed to mimic the results of simulations by reducing computational costs. In order to reduce the amount of computational time consumed, a novel framework for building efficient surrogate models is proposed in this work. The novelty lies in that the new framework runs simulations using the different simulation time spans for different inputs and builds a comprehensive surrogate model through the fusion of non-homogeneous spatio-temporal data by integrating the temporal and spatial correlations in parametric space. This differs from the existing works in the literature, which only consider the situation of spatio-temporal data with a consistent time span during simulations under different inputs. Some simulation studies and real data analysis concerning the pollution of the river in the Sichuan Province of China are used to demonstrate the superior performance of the proposed methods.
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Macasieb, Reygie Quiñanola, Christian Rodriguez Orozco, and Augustus Cooper Resurreccion. "APPLICATION OF COUPLED HEC-HMS AND US EPA WASP FOR TRANSPORT MODELLING OF MERCURY IN THE MINING-IMPACTED AMBALANGA RIVER." ASEAN Engineering Journal 11, no. 3 (April 21, 2021): 158–76. http://dx.doi.org/10.11113/aej.v11.17052.
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This study provides a simulation of mercury (Hg) transport in water and sediments in the mining-impacted Ambalanga River located in Upper Agno Subbasin in the Philippines. The Hydrologic Engineering Center - Hydrologic Modeling System (HEC-HMS) and Water Quality Analysis Simulation Program (WASP) of the US Environmental Protection Agency (EPA) were coupled to handle both hydrologic modelling and total Hg transport processes, respectively, for 12 months in the year 2014. Watershed delineation from Digital Elevation Model, rainfall and streamflow data from the local weather bureau, and dam operational data were used to develop the hydrological model. The calibrated HEC-HMS model satisfactorily simulated the flow in the river and its tributaries, which is then used as an input to the Hg transport model. The Ambalanga subbasin was conceptually divided into 29 segments in WASP to represent the water column and the surface benthic sediment. Time-variable sediment and Hg load were applied to the upstream of Ambalanga River. Total Hg concentration in water and sediments at five sampling locations along the Ambalanga River and two sampling locations along the Upper Agno River were measured in 2014-2015, in addition to the Hg monitoring data from the local environmental bureau. The gathered data were used to validate the WASP model, and results show that it was able to reasonably simulate the Hg fate and transport. Simulation results showed a downward trend in Hg concentration in surface water and sediments from upstream to downstream, while Hg in sediments was observed to stabilize over time. The model was further utilized to come up with exceedance curves of Hg in water and sediments as a result of the river’s response to different Hg loading from the known point sources. The exceedance curves derived from the model were used to determine the maximum permissible Hg loading to the river and identify pollution load reduction measures for river rehabilitation.
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Li, Ming Chao, and Fei Liu. "Slope Instability Assessment Based on 3D Slope Model and Numerical Simulation Analysis." Advanced Materials Research 243-249 (May 2011): 4675–79. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.4675.
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Based on an actual slope in the Three Gorges reservoir, the 3D geological model was built as the foundation. The numerical simulation method of the slope instability process was put forward. Then, a series of dynamic parameters were computed, including stability factors, accelerations, velocities, displacements. And the hazards of surge and river-blocking were analyzed. It offers a new analytical approach to the reservoir slope instability.
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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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Wu, Xinyu, Rui Guo, Xilong Cheng, and Chuntian Cheng. "Combined Aggregated Sampling Stochastic Dynamic Programming and Simulation-Optimization to Derive Operation Rules for Large-Scale Hydropower System." Energies 14, no. 3 (January 26, 2021): 625. http://dx.doi.org/10.3390/en14030625.
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Simulation-optimization methods are often used to derive operation rules for large-scale hydropower reservoir systems. The solution of the simulation-optimization models is complex and time-consuming, for many interconnected variables need to be optimized, and the objective functions need to be computed through simulation in many periods. Since global solutions are seldom obtained, the initial solutions are important to the solution quality. In this paper, a two-stage method is proposed to derive operation rules for large-scale hydropower systems. In the first stage, the optimal operation model is simplified and solved using sampling stochastic dynamic programming (SSDP). In the second stage, the optimal operation model is solved by using a genetic algorithm, taking the SSDP solution as an individual in the initial population. The proposed method is applied to a hydropower system in Southwest China, composed of cascaded reservoir systems of Hongshui River, Lancang River, and Wu River. The numerical result shows that the two-stage method can significantly improve the solution in an acceptable solution time.
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Pintér, György G. "The Danube Accident Emergency Warning System." Water Science and Technology 40, no. 10 (November 1, 1999): 27–33. http://dx.doi.org/10.2166/wst.1999.0498.
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Significant number of accidental water pollution incidents occurred during the past decades in the Danube River Basin, often having transboundary impacts. Growing needs arose at the important water users (first of all at drinking water intakes) along the rivers to get early warning about such incidents. The Danube Accident Emergency Warning System (DAEWS) was put into operation in April 1997, as a result of the short term priority action of the Environmental Programme for the Danube River Basin. The Danube Accident Emergency Warning System provides immediate information on sudden changes in water characteristics, like accidental river pollution incidents having transboundary effects, to assist the responsible authorities and water users in the downstream countries to make preventive measures in time. The countries where the system is now operational are (in the order of their location in the river basin): Germany, Austria, Czech Republic, Slovakia, Hungary, Slovenia, Croatia, Romania, and Bulgaria. The National Centres of the system established within the programme in each of the co-operating countries are called as PIACs (Principal International Alert Centres), being in close contact with the national pollution control structures. To meet the requirements on fast information transmission capabilities, the system are equipped with a satellite communication system linked to local computer network between the units of the PIACs with information processing system, hazardous substances database, the Danube Basin Alarm Model for the simulation of pollution effects. International Operation Manual provides the standard operation technique in each country. Practical example of the serious chemical accidental spill in Hungary in May 1998 illustrates the operation of the DAEWS system.
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Souhar, Otmane, and Jean-Baptiste Faure. "Approach for uncertainty propagation and design in Saint Venant equations via automatic sensitive derivatives applied to Saar river." Canadian Journal of Civil Engineering 36, no. 7 (July 2009): 1144–54. http://dx.doi.org/10.1139/l09-057.
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This paper describes the assessment of uncertainties of computational fluid dynamics (CFD) for modelling free surface flows. A series of CFD simulations, using MAillé GEnéralisé (MAGE), are employed to compute the flood extent resulting from the overflow of rivers. These simulated outputs are affected by uncertainties in the empiric roughness coefficients. Uncertainty propagation in MAGE outputs is difficult to evaluate because of the complexity and the nonlinearity of models. Assessment of uncertainties may be carried out by computing derivatives of the output results with respect to the inputs. Recently, automatic differentiation (AD) has become an efficient numerical method for sensitivity analysis and assessment of uncertainties. In this paper, AD is used to transform mechanically a given one-dimensional hydraulic model, MAGE, into a new program capable of computing the original simulation and the desired derivatives. Specifically, derivatives of the flood extent and the water width with respect to the roughness coefficients are computed. Numerical experiments of derivatives obtained from AD and divided difference (DD) approximations are compared, validating derivatives obtained by AD. Results can serve to evaluate existing flood models.
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Othman, Faridah, M. E. Alaa Eldin, and Mustaffa K. Mohd Nor. "Assesment of a Tropical Urban River Using GIS-Based Modeling." Advanced Materials Research 250-253 (May 2011): 2949–52. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.2949.
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The Klang River originates from the northern part of Selangor, drains the Klang Valley, and finally discharges itself into the Straits of Malacca, approximately 120 km away from the upstream point. As the state of Selangor and the city of Kuala Lumpur are going through tremendous development, the river is subjected to pollution from point and non-point sources. The pollution sources may come from urban activities, agricultural activities, industrial and commercial activities, and residential areas. In addition to this, the pollution loading from non-point sources is usually difficult to estimate because it is a function of rainfall/storm water runoff. The purpose of this research is to set-up a digitized model of the Klang Valley river basin to study the effect of development on the river basin by using computer modeling. In this paper, the used of GIS technique in determining the spatial variability in river basin has been explored. Based on the GIS technique, the DEM of the study basin was used to delineate the stream network and extract information of catchments characteristics. The locations of the point and non-point sources were surveyed and digitized spatially along the river basin. These are important as it will serve as a database before the water quality simulation can be performed. The developed model can also be extended to a larger basin. Field survey and further investigations would be helpful in calibrating the critical parameters and thus improving performance of the developed model.
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Li, Zongyu, Zhilin Sun, Jing Liu, Haiyang Dong, Wenhua Xiong, Lixia Sun, and Hanyu Zhou. "Prediction of River Sediment Transport Based on Wavelet Transform and Neural Network Model." Applied Sciences 12, no. 2 (January 10, 2022): 647. http://dx.doi.org/10.3390/app12020647.
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The sedimentation problem is one of the critical issues affecting the long-term use of rivers, and the study of sediment variation in rivers is closely related to water resource, river ecosystem and estuarine delta siltation. Traditional research on sediment variation in rivers is mostly based on field measurements and experimental simulations, which requires a large amount of human and material resources, many influencing factors and other restrictions. With the development of computer technology, intelligent approaches have been applied to hydrological models to establish small information in river areas. In this paper, considering the influence of multiple factors on sediment transport, the validity of predicting sediment transport combined with wavelet transforms and neural network was analyzed. The rainfall and runoff cycles are extracted and decomposed into time series sub-signals by wavelet transforms; then, the data post-processing is used as the neural network training set to predict the sediment model. The results show that wavelet coupled neural network model effectively improves the accuracy of the predicted sediment model, which can provide a reference basis for river sediment prediction.
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Cacal, Jennifer C., Victor Czar A. Austria, and Evelyn B. Taboada. "Extreme Event-based Rainfall-runoff Simulation Utilizing GIS Techniques in Irawan Watershed, Palawan, Philippines." Civil Engineering Journal 9, no. 1 (January 1, 2023): 220–32. http://dx.doi.org/10.28991/cej-2023-09-01-017.
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River flow assessments and ecologically sustainable water management plans are now possible due to the advancement of sophisticated computer models. The US Army Corps of Engineers developed the HEC-HMS model, which can be used for various hydrological simulations. Rainfall-runoff modeling aids in estimating peak flows, which is critical for water resource management planning. On December 18, 2017, a heavy rainfall event in the ungauged Irawan basin in Puerto Princesa City, Palawan, Philippines, was simulated to determine the peak flow and amount of water. The current research aims to construct a rainfall-runoff simulation model. A specific hyetograph is used to make the hydrographs for the basin. This study utilizes ArcGIS and QGIS, which perform the geospatial analysis and provide the HEC-HMS model's hydrologic modeling inputs. The hydrological parameters were determined using soil type, land use, and land cover maps. Incorporating SCS loss, Clark unit hydrograph, and Muskingum flow routing, HEC-HMS was employed in the rainfall-runoff simulation. Rainfall data corresponding to the recorded streamflow was used to calibrate and validate the parameters. Several performance metrics, including Nash-Sutcliffe efficiency (NSE) and Percentage Bias (PBIAS), were utilized to evaluate the overall effectiveness of the system. An effective decision-making and warning system can be implemented using the developed model. Doi: 10.28991/CEJ-2023-09-01-017 Full Text: PDF
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Zhan, Xiaoyong. "Simulation of unsteady flow and solute transport in a tidal river network." Engineering Computations 20, no. 5/6 (August 2003): 754–67. http://dx.doi.org/10.1108/02644400310488853.
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Thollapalli, Ashok, Gary C. April, Donald C. Raney, William W. Schroeder, Barry C. McCormick, and Zhaodong Lu. "Computer Simulation of the Hydrodynamic and Salinity Behavior of Weeks Bay, Alabama, at Equatorial Tide Conditions." Water Science and Technology 24, no. 6 (September 1, 1991): 165–69. http://dx.doi.org/10.2166/wst.1991.0153.
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Whereas the long term goal of the work described focuses on issues related to estuaries in general, specific attention in this paper focuses on one – Weeks Bay, Alabama. This estuary is one of seventeen estuarine research reserves established as “natural field laboratories” for long-term scientific and educational programs (See Figure 1). Initially, Weeks Bay will be assumed to be a well mixed estuary such that two-dimensional (depth averaged) modeling can be used. The Waterways Experiment Station Implicit Flooding Model (WIFM), developed by the U.S. Army Corps of Engineers, Vicksburg, Mississippi is used. Complete data sets at equatorial tidal conditions were chosen from the field data available. Good agreement of model results with field measured water elevations was noted. These results are typical of the kind of agreement that is expected from two-dimensional depth averaged model simulations. As anticipated, there seems to be little or no movement of salt along the western shoreline when the Bon Secour Bay salinities are low. This indicates selective flow of Fish River water down the western side of the bay with a corresponding preference for Bon Secour Bay water to flow along the eastern shore.
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Üneş, Fatih, Yunus Ziya Kaya, Hakan Varçin, Mustafa Demirci, Bestami Taşar, and Martina Zelenakova. "Flood Hydraulic Analyses: A Case Study of Amik Plain, Turkey." Water 12, no. 7 (July 21, 2020): 2070. http://dx.doi.org/10.3390/w12072070.
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In recent years, significant flood events have occurred in various parts of the world. The most important reasons for these events are global warming and consequent imbalances in climate and rainfall regimes. Many studies are performed to prevent the loss of life and property caused by floods. Many methods have been developed to predict future floods and possible affected areas. Developing computer and numerical calculation methods gives opportunities to make simulations of flood hazards. One of the affected areas, which is also one of the world’s first residential districts at Hatay in Turkey, is the Amik Plain. In this study, the floods on the Amik Plain in Hatay province are analyzed. Hatay airport was also affected during floods since 2012 and serious material damage occurred. For this purpose, Google Earth Pro software was used to obtain maps of the basin where the airport is located and the rivers it contains. Afterwards, Hydrologic Engineering Center’s River Analysis System module (HEC-RAS) was used for the hydraulic and hydrological definitions of the river basin. The results of numerical models are presented as simulated maps.
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Honnorat, Marc, Jérôme Monnier, and François-Xavier Le Dimet. "Lagrangian data assimilation for river hydraulics simulations." Computing and Visualization in Science 12, no. 5 (March 26, 2008): 235–46. http://dx.doi.org/10.1007/s00791-008-0089-x.
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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.
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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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Dempsey, Paul, Andy Eadon, and Gerard Morris. "Simpol: a simplified urban pollution modelling tool." Water Science and Technology 36, no. 8-9 (October 1, 1997): 83–88. http://dx.doi.org/10.2166/wst.1997.0648.
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In the UK, the standards which protect river aquatic life against the effect of short term intermittent pollution events are expressed in terms of river concentration/duration thresholds for return periods ranging from 1 month to 1 year. To demonstrate compliance with these standards, it is necessary to simulate the performance of a drainage system and the river impact for a number of wet weather events, chosen such that the return periods of critical concentrations/durations can be estimated with confidence. Many events must be simulated leading to long computer runs and large result files when using detailed simulation models. This paper describes how this problem has been addressed within the UK Urban Pollution Management procedure by developing a simplified urban pollution model called SIMPOL. This model is designed to represent the key urban processes in a relatively simple way. Accuracy is preserved by calibrating the model against a small number of detailed model results. As multiple runs can be carried out easily, SIMPOL modelling allows greater account to be taken of the variability in rainfall, river conditions and foul flow quality. Potential solutions can be rapidly tested against both environmental and emission standards. A case study is used to illustrate the application of SIMPOL.
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Noordin, M. N. A., R. M. Hudzari, S. M. Sapuan, and M. A. H. A. Ssomad. "Design, Analysis and Fabrication of Conceptual Innovative Hand Tool." Applied Mechanics and Materials 564 (June 2014): 752–57. http://dx.doi.org/10.4028/www.scientific.net/amm.564.752.
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Dioscorea hispida is a poisonous plant normally found in forest where scientific studies have shown that its tuber contains toxic poison and can be consumed after its poison is removed. Traditionally the tubers were placed in flowing river water for several days. In the harvesting aspect, an innovative hand tool were conceptually designed to replace the traditional hoe or “cangkul”. Using IMADA digital force gauge to measure the force required for pulling out the tuber and reverse engineering methods, an innovative hand tool were designed and developed. The results from experiments showed that the force required for harvesting the Dioscorea hispida tuber is found significant with its weight versus regression squared (R2) of 0.86. The information of optimum force required from field experiment is used to model the simulation and practicality in Computer Aided Design (CAD) environment system. The finite element on stress distribution on selected material of hand tool was simulated by uploading the material characteristic on simulation program embedded in Solidworks software. The end result of the simulation is based on visualization of analysis in Solidworks while producing the hand tool for designing and fabrication from material which is lighter and stronger.
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Lim, King Hann, Kah Phooi Seng, and Li-Minn Ang. "River Flow Lane Detection and Kalman Filtering-Based B-Spline Lane Tracking." International Journal of Vehicular Technology 2012 (November 5, 2012): 1–10. http://dx.doi.org/10.1155/2012/465819.
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A novel lane detection technique using adaptive line segment and river flow method is proposed in this paper to estimate driving lane edges. A Kalman filtering-based B-spline tracking model is also presented to quickly predict lane boundaries in consecutive frames. Firstly, sky region and road shadows are removed by applying a regional dividing method and road region analysis, respectively. Next, the change of lane orientation is monitored in order to define an adaptive line segment separating the region into near and far fields. In the near field, a 1D Hough transform is used to approximate a pair of lane boundaries. Subsequently, river flow method is applied to obtain lane curvature in the far field. Once the lane boundaries are detected, a B-spline mathematical model is updated using a Kalman filter to continuously track the road edges. Simulation results show that the proposed lane detection and tracking method has good performance with low complexity.
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Wise, MSCE, EIT, Richard, Andrew Darnell, MSCE, EIT, and John Quaranta, PhD, PE. "Critical review of Terrain Tile and Google Earth: Virtual image mapping methods for floodplain management." Journal of Emergency Management 10, no. 6 (March 21, 2018): 433. http://dx.doi.org/10.5055/jem.2012.0120.
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Inundation mapping is a major component of floodplain management, providing critical information as to the consequences of potential failures of flood control structures. Flood mitigation efforts rely on the creation of inundation maps to develop appropriate response measures for crisis situations, including dam failures. To develop inundation maps, a dam and river system is modeled with engineering computer programs, and a simulation of the dam failure is performed to generate data for the flood. This output data are input into other programs to develop inundation maps. Inundation maps have traditionally been produced in a paper format, but recent advances in computer modeling have provided the capability for virtual inundation maps. Virtual inundation maps offer new methods of presentation and analysis of flood impacts; thus, these mapping methods need to be investigated to determine the applications and relevance to floodplain management. The goal of this research is to advance the development and use of inundation maps by floodplain managers and emergency agencies. A simulation of a potential dam failure was performed using computer modeling for a candidate river system, and the inundation maps were created using two procedures: Terrain Tiles and Google Earth. An analysis of the strengths and weaknesses of each mapping procedure was conducted. The results indicated that the Terrain Tiles procedure has advantages in displaying critical information, such as arrival times and water depths. However, this mapping procedure is more labor intensive, and the online file sharing may not be accessible for all users. The strengths of the Google Earth procedure include two-dimensional and three-dimensional views for analysis, user-friendly file sharing, and the inclusion of built-in critical infrastructure and terrain data. Drawbacks of this procedure are that the inundation must still be generated in ArcGIS, the display of critical information is not as clear, and the online file sharing may pose security issues. Thus, the Terrain Tiles procedure should be used for the development of emergency response measures, and the Google Earth procedure should be used by emergency responders in the event of an actual emergency.
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Sowinski, Marek, and Anna Neugebauer. "CALIBRATION OF WATER‐QUALITY MODEL “WODA” – CASE STUDY OF THE WARTA RIVER." JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 15, no. 2 (June 30, 2007): 93–98. http://dx.doi.org/10.3846/16486897.2007.9636914.
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The main feature of the proposed model implemented by a computer package WODA, that distinguishes it from other commonly used models like QUALE 2E or WASP5, is a possibility of its automatic calibration i e parameter estimation taking into account simultaneously several sets of measured concentration data. Model WODA, developed by A. Kraszewski and R. Soncini‐Sessa, enables fitting simulated values to measured concentrations of BOD and DO based on the least‐square criterion. This model was applied for parameter estimation of the Warta River in Poland. Measured concentration data used for parameter estimation were obtained from monthly monitoring. The results are presented in the form of BOD and DO lines against measured concentrations along the analysed stretch of the Warta River. Adaptation of the model simulation results to measured data is described by quantifying characteristics. They indicate relatively good adjustment. The reasons of some differences are discussed and explained.
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Formetta, Giuseppe, Ilaria Prosdocimi, Elizabeth Stewart, and Victoria Bell. "Estimating the index flood with continuous hydrological models: an application in Great Britain." Hydrology Research 49, no. 1 (June 7, 2017): 123–33. http://dx.doi.org/10.2166/nh.2017.251.
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Abstract Estimating peak river discharge, a critical issue in engineering hydrology, is essential for designing and managing hydraulic infrastructure such as dams and bridges. In the UK, practitioners typically apply the Flood Estimation Handbook (FEH) statistical method which estimates the design flood as the product of a relatively frequent flow estimate (the index flood, IF) and a regional growth factor. For gauged catchments the IF is estimated from observations. For ungauged catchments it is computed through a multiple regression model. While the FEH IF method provides peak flow estimates that are statistically robust, it does not readily take into account catchment heterogeneity or effect of environmental change on river flows. This study presents a new methodology to estimate the IF at national scale using continuous simulation from a physically based hydrological model (Grid-to-Grid). The methodology is tested across Great Britain and compares well with IF estimates at 550 gauging stations (R2 = 0.91). The promising results for Great Britain support the aspiration that continuous simulation from large-scale hydrological models coupled with increasing availability of global weather and climate products, could be used to estimate design floods in regions with limited gauge data or affected by environmental change.
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Wang, Xin Jie. "Research and Application of Lost Foam Technology of Goods Train Low-Carbon Alloy Steel Casting." Advanced Materials Research 284-286 (July 2011): 2340–49. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.2340.
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Apply an organic whole technological medium of computer aided three dimensions design 、computer aided solidification process numerical value simulation engineering ＆ computer aided numerical control programming manufacturing, by means of optimization product pattern structure、foundry processing parameters 、die auxiliary equipment and tool、riser gating system ＆ die cavity numerical control cutter location source file , the type of Z8A goods train low-carbon alloy adapter lost foam casting has been under development .Compare lost foam technology to ordinary sand mold casting ,the casting monomer weight lightened 3kg , grade of casting weight precision come to MT7 , grade of casting size precision come to CT8 ,foundry processing yield come to 65% ；Casting defects easily appeared in the course of large quantities production has been analysed ＆ offered solution methods in this article.
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Wan, Zhanhong, Zongfu Ren, Xiaochun Wang, and Honghao Zheng. "Application of unstructured grid finite-volume coastal ocean model (FVCOM) to the Yangtze River hypoxic zone." International Journal of Numerical Methods for Heat & Fluid Flow 26, no. 8 (November 7, 2016): 2410–18. http://dx.doi.org/10.1108/hff-07-2015-0259.
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Purpose To observe the relations between three important factors resulting in estuarial Hypoxia phenomena of Yangtze River – wind, river flow, and stratification. The purpose of the paper is to analyze the possible reasons why hypoxia occurs in late spring and disappears in October. Design/methodology/approach To overcome the difficulty in examining the role of physical and biological factors affecting hypoxia based on measurement alone, finite-volume community ocean model (FVCOM) was introduced into the investigation. Observed freshwater flux data from Yangtze River, monthly averaged wind speed data, and other observed data were input into the model; the accuracy of which was validated with various kinds of data. The authors used the trajectories of Lagrangian particles from Yangtze River to study the regions of strong riverine influence under different wind forcing conditions and compared the simulation results with former observations. Findings Trade wind is a significant factor to influence the forming and receding of hypoxia across the Yangtze River. Originality/value Using FVCOM to investigate estuary hypoxia is more economical and effective.
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Gordillo, Geovanny, Mario Morales-Hernández, and Pilar García-Navarro. "Finite volume model for the simulation of 1D unsteady river flow and water quality based on the WASP." Journal of Hydroinformatics 22, no. 2 (November 15, 2019): 327–45. http://dx.doi.org/10.2166/hydro.2019.080.
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Abstract In this work, a one-dimensional (1D) finite volume numerical model for the unsteady simulation of the flow hydrodynamics and water quality is developed. The water dynamics is formulated with the 1D shallow water equations, and the water quality evolution is described by the Water Quality Analysis Simulation Program (WASP) model, allowing us to interpret and predict the transport and fate of various biochemical substances along any river reach. This combined system is solved with an explicit finite volume scheme based on Roe's linearization for the advection component of both the flow and the solute transport equations. The proposed model is able to consider temporal variations in tributaries and abstractions occurring in the river basin. This feature is transcendent in order to predict the chemical composition of natural water bodies during winter and summer periods, leading to an improvement in the agreement between computed and observed water quality evolutions. The combined model has been evaluated using literature tests in a steady state and a real-field case of the Ebro river (Spain), characterized by a marked unsteady regime. In the real case, we found that the water temperature was very sensitive to both the solar radiation and the average air temperature, requiring a careful calibration of these parameters. The numerical results are also demonstrated to be reasonably accurate, conservative and robust in real-scale field cases, showing that the model is able to predict the evolution of quality parameters as well as hydrodynamic variables in complex scenarios.
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Tseng, Chien-Yung, and Yi-Ju Chou. "Nonhydrostatic simulation of hyperpycnal river plumes on sloping continental shelves: Flow structures and nonhydrostatic effect." Ocean Modelling 124 (April 2018): 33–47. http://dx.doi.org/10.1016/j.ocemod.2018.02.003.
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Chen, Alex, Jérôme Darbon, Carlo De Franchis, Gabriele Facciolo, Enric Meinhardt, Julien Michel, and Jean-Michel Morel. "Numerical simulation of landscape evolution and water run-off on digital elevation models obtained from Pleiades." Revue Française de Photogrammétrie et de Télédétection, no. 209 (February 4, 2015): 117–23. http://dx.doi.org/10.52638/rfpt.2015.135.
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This paper illustrates how the main physical laws proposed in landscape evolution models (LEMs) can be modeled by a system of three partial differential equations governing water run-off, stream incision, hill slope evolution and sedimentation. Several numerical experiments on high resolution digital elevation models (DEMs) obtained from image stereo pairs of the satellite Pleiades illustrate its potential to simulate the fine structure of the river network, and to understand the landscape morphology and its causes.
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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.
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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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Xie, Dong, and Kun Li. "Comprehensive Evaluation of Thermal Comfort in Ship Cabins: A Case Study of Ships in Yangtze River Basin, China." Buildings 12, no. 10 (October 21, 2022): 1766. http://dx.doi.org/10.3390/buildings12101766.
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In recent years, the waterway navigation and transportation industry has been developing rapidly, and the living environment of ship cabins has not received much attention. Using questionnaire surveys, data collection and computer simulations, this study explored the problems and causes related to thermal comfort that affect a crew living onboard. The survey showed differences in the thermal sensations of the crew. Cabins below the deck of a ship are usually more comfortable than those above deck. These differences were related to the range of frequent activities undertaken in the cabins. The data and calculations show that the thermal comfort in the stern winch cabin and the engine cabin was significantly higher than in the top living cabin and the meeting cabin. For cabins without windows in winter, the PMV and PPD indexes of those below deck were on average 11.95% higher and 7.03% lower, respectively, than those above deck, indicating better overall thermal comfort below deck. The simulation showed that the simulated PMV of an occupied cabin was up to 17.55% higher than the actual PMV, indicating that the number of crew members in the cabin significantly affected its level of thermal comfort. The results provide a reference for understanding and improving the thermal environment of ships and temporary water facilities.
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Han, Xing, Bing Zhu, Jun Ping Wang, and Gui Man Liu. "Coupled Vibration Analysis of Vehicle-Bridge System for Jinsha River Bridge." Applied Mechanics and Materials 361-363 (August 2013): 1194–98. http://dx.doi.org/10.4028/www.scientific.net/amm.361-363.1194.
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Numerical simulation model to analyze the coupling vibration between vehicle and bridge established in this paper, upon the engineering background of Jinsha River Bridge. The finite element commercial software, ANSYS, is employed to set up the dynamic analysis model and to compute its natural vibration characteristics. Then CRH3 special refined model is built with SIMPACK, a multi-body dynamics commercial software. Considering the factors like track-rail irregularity, the dynamic performance of bridge and driving comfort level are obtained. The analysis results of coupled vibration demonstrate that bridge bears sufficient stiffness due to its satisfying vibration performance; the safety in operation of vehicle meets the requirement with the comfort index of "good". All the results not only provide reference for design, but also work as the theoretical basis for future design of similar bridges. The paper is deemed a s evidence of the priority of bridge-vehicle model by finite element method and multi-body dynamics method. The process of modeling turns to be stylized, which avoids the unnecessary programming for individual project.
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Timbe Castro, Luis Manuel, Patricio Javier Crespo Sánchez, and Juan José Cabrera-Balarezo. "Evaluation of the HEC-HMS model for the hydrological simulation of a paramo basin." DYNA 86, no. 210 (July 1, 2019): 338–44. http://dx.doi.org/10.15446/dyna.v86n210.70738.
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In this study, the performance of the HEC-HMS model was evaluated for the simulation of rain-runoff processes in a paramo basin of approximately 21. 8 km2, south of Ecuador. The calibration and validation comprises the period of July-2013 to June-2016 with daily data. The Soil Moisture Accounting (SMA) method was used to compute the water flow in the soil. For the rainfall distribution, the Thiessen method was used, while the Evapotranspiration was calculated with the Penman-Monteith equation. The results revealed that (1) 83% of the water infiltrates the soil while only 17% is retained in plants and the soil surface, (2) the water is retained for approximately 42 days before reaching the river and (3) that more than 60% of the flow corresponds to sub-surface flow.
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Funamizu, N., T. Iwamoto, and T. Takakuwa. "Mathematical model for describing reactions of residual chlorine with organic matter in reclaimed wastewater." Water Science and Technology 50, no. 2 (July 1, 2004): 195–201. http://dx.doi.org/10.2166/wst.2004.0123.
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Among several applications of urban wastewater reuse, use of reclaimed wastewater to sustain stream flows has become attractive in the urban area. Since these rivers are used for recreational purposes and for restoring aquatic eco-system, the adequate control of residual chlorine is essential. Mathematical model for describing reactions between residual chlorine and organic matter in reclaimed wastewater has been developed. The model considers the effect of molecular weight distribution of organic matter on the reaction rate. Lab-scale experiments were performed to estimate reaction rates constants and to examine their temperature dependency. The experiments showed that 1) the smaller organic matter gave the larger reaction rate; 2) temperature effect on reaction rate was described by the Arrhenius formula; 3) decline of free chlorine had more temperature dependency than combined chlorine. The comparison of computed results with data from lab-scale experiments confirmed the validity of the model. We used the one-dimensional dispersion model with proposed reaction model and examined the seasonal variation of residual chlorine profile along the river sustained by reclaimed wastewater in Sapporo. Simulation showed that seasonal variation of nitrification performance in secondary treatment as well as change in temperature caused seasonal variation in residual chlorine profile along the river.