Shape Optimization Of Vertical Pipe Inlet/Outlet And Research Of Y-type Tube In Pumped-Storage Plant

Both vertical pipe inlet/outlet and Y-type tube have the characteristic of two-flow directions in water flow system of Pumped-Storage Plant, So they are very important for optimum design and plant's economical benefit and safety. The research on Y-type tube and optimizing the shape of vertical pipe inlet/outlet in Pumped-Storage Plant, integrated with project case, theoretical analysis, numerical simulation and model experiments. Model experiments of the shape optimization of vertical pipe inlet/outlet include head loss coefficients and velocity of flow and vortex flow and so on. Model simulation of shape optimization of vertical pipe inlet/outlet pay attention to inside flow and reducing cases, and so on; while model simulation of Y-type tube includes head loss coefficients, point tress, velocity of flow, and so on. 3-D numerical simulation of Y-type tube particularly emphasizes on velocity field and pressure distribution. That is, both numerical simulation and model experiments are complemental to each other. The main point of the thesis are as following:1. Vertical pipe inlet/outlet is simplified as an axisymmetric model in the research, and flow field is simulated with second-moment Reynolds stress model and VOF. Numerical result describes flow characteristics of diffuser pipe and lockage gate etc. Model test shows that the method is reliable, and accuracy of the numerical model is approximate to 3-D numerical model, which is helpful for shape optimization. So, numerical simulation improves efficiency of the model experiments efficiency.2. According to the computed results, model experiments compared various shapes of vertical pipe inlet/outlet in headless, velocity and vortex. A rational and safe vortex-proof ladder was created and was provided for further projects.3. Mathematical calculation adopted turbulence model of Reynolds stress equation, finite volume method and second-order upwind scheme; while couplingnumeration of velocity field and tress was based on Simplec. It showed that the calculation result is in good accord with the experimental data. Thus the research result is reliable.4. A series of hydraulic model experiments of water flow, head loss and tress of Y-type tube under various conditions were carried out for validating the fork tube. Secondary flow was found and successfully simulated in numerical simulation. Results of the model experiments greatly support for Y-type tube and other water flow researches.