Experimental Study And Numerical Simulation On Hydraulic Characteristics Of Bottom Outlet

With the development of economy in recent years, our country built a lot of water conservancy engineering facilities in the river. These projects can flood detention river protection against floods, at the same time can provide clean cheap electricity, provide guarantee for economic development. In the study of large water conservancy hub project, the hydraulic characteristics of flood discharge building is worthy of further research direction. Flood discharging buildings is mainly used for venting excess waterfrom upper stream, its mainly type include spillway, bottom outlet, hydraulic tunnel, sluice gate and combine used facilities.Before the 21st century the hydraulic characteristics of flood discharge building research mainly depend on the physical model test. With the improving of the computer performance and the development of computational fluid dynamics, numerical simulation technology to overcome the model test time-consuming and difficult to obtain the flow field in the whole domain hydraulic data such as faults, increasingly widely used in engineering, has gradually become the important supplementary means of physical model test. Based on the physical model test and numerical simulation method of combining the study of hydraulic characteristics of flood and bottom outlet, the work is mainly as follows:(1)This paper introduces the research on water bottom outlet, meaning and the purpose of the present research situation;(2)Introduces the basic theory of numerical simulation of turbulent flow, briefly in troducting the basic governing equations numerical algorithm, common turbulence mod el, numerical simulation method of the free surface flow numerical computation metho d(3) Describes the present situation of a water conservancy hub project, combined with the actual project water bottom outlet for the hydraulic model test, introduces the model test of model design, installation, data measuring, need to pay attention to, obtained the discharge flow, surface elevation, flow rate and bottom pressure data of the water bottom outlet.(4) Based on Fluent commercial software, a 3-D flow field numerical simulation from the bottom outlet was established in order to fully research the hydraulic characteristics of the bottom outlet, in which the standard k?? turbulence model and the volume fraction method (VOF) on free surface tracking technology were used. The hydraulic characteristics such as free water surface, pressure field and velocity of the bottom outlet were achieved under the design flood level and the check flood level. The results of the simulated calculation were compared and analyzed with the model test data, and good agreements were obtained. The numerical simulation of the bottom outlet water discharge process is feasible.