1-D and 2-D mathematical models for dam break flow were established and verified with the measured data in laboratory. The 1-D and 2-D models were then coupled, and used to simulate the dam break flow from the reservo...1-D and 2-D mathematical models for dam break flow were established and verified with the measured data in laboratory. The 1-D and 2-D models were then coupled, and used to simulate the dam break flow from the reservoir tail to the dam site, the propagation of dam break waves in the downstream channel, and the submergence of dam break flow in the downstream town with the hydrodynamics method. As a numerical example, the presented model was employed to simulate dam break flow of a hydropower station under construction. In simulation, different dam-break durations, upstream flows and water levels in front of dam were considered, and these influencing factors of dam break flow were analyzed, which could be referenced in planning and designing hydropower stations.展开更多
Navigable flow condition simulations can provide detailed information on water depth and velocity distribution, simulation speed is one of the key factors which influence real-time navigation. In this paper, a navigab...Navigable flow condition simulations can provide detailed information on water depth and velocity distribution, simulation speed is one of the key factors which influence real-time navigation. In this paper, a navigable flow condition simulation system is developed to provide useful information for waterway management and shipping safety. To improve the simulation speed of 2-D hydrodynamic model, an explicit finite volume method and Open MP are used to realize parallel computing. Two mesh schemes and two computing platforms are adopted to study the parallel model＇s performance in the Yangtze River, China. The results show that the parallel model achieves dramatic acceleration, with a maximum speedup ratio of 34.94？. The parallel model can determine the flow state of the navigable channel in about 4 min, efficiency is further improved by a flow simulation scheme database. The developed system can provide early warning information for shipping safety, allowing ships to choose better routes and navigation areas according to real-time navigable flow conditions.展开更多
In this paper, the erosion-resisting coefficient was introduced to computebed deformation in a crush bedrock river. In the case of crush bedrock, there has been no propercontrol equation to describe bed stability, whi...In this paper, the erosion-resisting coefficient was introduced to computebed deformation in a crush bedrock river. In the case of crush bedrock, there has been no propercontrol equation to describe bed stability, which leads to difficulty in calculation of the beddeformation with conventional methods. The data from field survey were used to give thee-rosion-resisting capability with an appropriate coefficient. After the determination oflongitudinal distribution expressed by polynomial regression and transversal distribution expressedby normal distribution function, the plane distribution of erosion-resisting coefficient in a crushbedrock river was obtained. With the computational results from a 2-D horizontal flow mathematicalmodel, the erosion-resisting coefficient and controlling condition of local stability were employedto compute the values of bed deformation when riverbed is stable. The above method was applied in acase study, and the computational results of flow and bed deformations are in good a-greement withphysical model test data.展开更多
In regions with broad water surfaces such as lakes, reservoirs and coastal areas, the wind stress on the flow motion generates a significant impact. The wind stress is an unsteady force which makes numerical simulatio...In regions with broad water surfaces such as lakes, reservoirs and coastal areas, the wind stress on the flow motion generates a significant impact. The wind stress is an unsteady force which makes numerical simulation difficult. This paper presents a two-dimensional （2-D） mathematical model of the impact of wind-induced motion on suspended sediment transport at Beijing＇s 13-Ling Reservoir. The model uses the Diagonal Cartesian Method （DCM） with a wetting-drying dynamic boundary to trace variations in the water level. The calculation results have been tested against in situ measurements. The measurements confirm the model＇s accuracy and agreement with the actual situation at the reservoir. The calculations also indicate that wind stress holds the key to suspended sediment transport at Beijing＇s 13-Ling Reservoir, especially when westerly winds prevail.展开更多
基金the National Basic Research Program of China(973 Program, Grant No. 2003CB415203)the National Natural Science Foundation of China (Grant No.50579054).
文摘1-D and 2-D mathematical models for dam break flow were established and verified with the measured data in laboratory. The 1-D and 2-D models were then coupled, and used to simulate the dam break flow from the reservoir tail to the dam site, the propagation of dam break waves in the downstream channel, and the submergence of dam break flow in the downstream town with the hydrodynamics method. As a numerical example, the presented model was employed to simulate dam break flow of a hydropower station under construction. In simulation, different dam-break durations, upstream flows and water levels in front of dam were considered, and these influencing factors of dam break flow were analyzed, which could be referenced in planning and designing hydropower stations.
基金Project supported by the 13th Five-Year National Key Research and Development Program of China(Grant No.2016YFC0401407)the 12th Five-Year National Key Tech-nology R&D Program(Grant No.2012BAB05B05)the National Natural Science Foundation of China(Grant No.51722901)
文摘Navigable flow condition simulations can provide detailed information on water depth and velocity distribution, simulation speed is one of the key factors which influence real-time navigation. In this paper, a navigable flow condition simulation system is developed to provide useful information for waterway management and shipping safety. To improve the simulation speed of 2-D hydrodynamic model, an explicit finite volume method and Open MP are used to realize parallel computing. Two mesh schemes and two computing platforms are adopted to study the parallel model＇s performance in the Yangtze River, China. The results show that the parallel model achieves dramatic acceleration, with a maximum speedup ratio of 34.94？. The parallel model can determine the flow state of the navigable channel in about 4 min, efficiency is further improved by a flow simulation scheme database. The developed system can provide early warning information for shipping safety, allowing ships to choose better routes and navigation areas according to real-time navigable flow conditions.
文摘In this paper, the erosion-resisting coefficient was introduced to computebed deformation in a crush bedrock river. In the case of crush bedrock, there has been no propercontrol equation to describe bed stability, which leads to difficulty in calculation of the beddeformation with conventional methods. The data from field survey were used to give thee-rosion-resisting capability with an appropriate coefficient. After the determination oflongitudinal distribution expressed by polynomial regression and transversal distribution expressedby normal distribution function, the plane distribution of erosion-resisting coefficient in a crushbedrock river was obtained. With the computational results from a 2-D horizontal flow mathematicalmodel, the erosion-resisting coefficient and controlling condition of local stability were employedto compute the values of bed deformation when riverbed is stable. The above method was applied in acase study, and the computational results of flow and bed deformations are in good a-greement withphysical model test data.
基金the National Natural Science Foundation of China (Grant Nos. 50325929 and 50221903).
文摘In regions with broad water surfaces such as lakes, reservoirs and coastal areas, the wind stress on the flow motion generates a significant impact. The wind stress is an unsteady force which makes numerical simulation difficult. This paper presents a two-dimensional （2-D） mathematical model of the impact of wind-induced motion on suspended sediment transport at Beijing＇s 13-Ling Reservoir. The model uses the Diagonal Cartesian Method （DCM） with a wetting-drying dynamic boundary to trace variations in the water level. The calculation results have been tested against in situ measurements. The measurements confirm the model＇s accuracy and agreement with the actual situation at the reservoir. The calculations also indicate that wind stress holds the key to suspended sediment transport at Beijing＇s 13-Ling Reservoir, especially when westerly winds prevail.
