The Numerical Simulation Of The River Flow On Urban Landscape River

As the construction of water ecologically-civilized city,the urban river planning and urban water system landscape design,etc.in the water conservancy of the people’s livelihood construction projects,attract more and more attention of people in the engineering.During the design of Landscape River,by considering the river function,such as flood control,drainage landscape and ecology,etc.,that often select the compound channel as the best choice of the form of the channel improvement.But the rainfall displays an uneven characteristic and the hydrological flow in flood and dry season will directly affects the river of the water landscape.In order to keep the river landscape,designers often built small practical weirs on Landscape River.For the problem that the small river landscape engineering limited to test expenses and test time,mostly only use hydraulic calculation,puts forward that using the method of numerical simulation instead of the physical model test to verify the hydraulic design scheme.Based on the river water system landscape design project in a certain city as the research background,the paper using FLUENT software makes three dimension numerical simulations to the flow state of the compound channel and the small weir flow over small practical weir,the main contents and research results are organized as follows:(1)It briefly introduces the basic control equations of 3-D turbulent flow numerical simulation and theory,numerical solution methods,the types of turbulence models and the free surface treatment technology.(2)Under the different flow rate,the numerical simulation research study the flow characteristics of compound channel with different cross-sections and different roughness(as different lining material),that obtains the velocity vector diagram,velocity contour map and the contour map and so on.From the analysis of calculating results it can be seen that the ideal lining material is concrete,the flow regime and hydraulic characteristics is ideal,meanwhile the results of the study provide certain value and reference function for engineering design.(3)In this paper,by using FLUENT software,based on the turbulence models and RNG k-epsilon turbulent model,and the finite volume method and non-uniform grid,VOF method to trace the free surface flow water,to simulation the weir flow of small weir.By comparing the right-angle import broad crested weir and bent weir flow chart of weir flow,the velocity vector diagram and flow velocity contour map and the pressure distribution,analysis the weir flow state of bent weir is better than the right-angle import broad crested weir,the simulation result is reasonable and reliable.