Complete bearing spiral case has not been applied to large power stations in China so far. The proposal of applying complete bearing spiral case necessitates an analysis of the reliability of the spiral case structure...Complete bearing spiral case has not been applied to large power stations in China so far. The proposal of applying complete bearing spiral case necessitates an analysis of the reliability of the spiral case structure and the security of units under various working conditions. In combination with practice of a project, this paper presents a three-dimensional nonlinear finite element static analysis of the concrete using a concrete smeared crack model by means of the well-known finite element method （FEM） software ABAQUS. The stress distribution of the spiral case and reinforcing bars, the range of damages in surrounding concrete, and the displacement of structure are quantified. The computational results indicate that the embedment method ensures the structure＇s safety in strength. At the same time, the result shows that this embedment is a kind of preponderant method for embedment in aspects of economy and technique of construction, and the application of this embedment method to the hydropower station is feasible provided that some proper engineering measures are taken to constrain the width of the concrete in accord with the code＇s requirements. The paper proves the security and reliability of the structural design of spiral case in hydropower station accordingly.展开更多
In consideration of the contact between the steel spiral casing and the peripheral reinforced concrete, a nonlinear analysis for the combined bearing structure of the JinPing-I preloading filling spiral case has been ...In consideration of the contact between the steel spiral casing and the peripheral reinforced concrete, a nonlinear analysis for the combined bearing structure of the JinPing-I preloading filling spiral case has been made with ANSYS. Contrasts of the stress of the reinforcing bars, the biggest width of the crack and the outspread section of the crack has been made with the different parameters of preloading pressure and reinforcement scheme, resulting in a reasonable preloading pressure and reinforcement scheme. This conclusion has been applied to the spiral casing of JinPing-I hydropower station.展开更多
As a key backbone project in developing and harnessing the Yangtze, the Three Gorges Project (TGP) is a largest water conservancy and hydropower project in China and all the world as well. With a huge comprehensive be...As a key backbone project in developing and harnessing the Yangtze, the Three Gorges Project (TGP) is a largest water conservancy and hydropower project in China and all the world as well. With a huge comprehensive benefit from flood control, power generation and navigation improvement, TGP, when completed, will exert a significant influence on the socio economic development across the Yangtze Basin and all China. Decisions on key technical issues concerning the construction of TGP were made on a huge number of scientific tests and verifications. The structural pattern selection of the penstock and the spiral case in the TGP power station is not only an important technical and economic issue, but also relating to the long term operation of the power station itself.展开更多
The spiral casing and stay vanes are important through flow parts of a hydraulic turbine.Their internal flows have significant influence upon the hydraulic efficiency and performance of the turbine. Based on the solut...The spiral casing and stay vanes are important through flow parts of a hydraulic turbine.Their internal flows have significant influence upon the hydraulic efficiency and performance of the turbine. Based on the solution of Navier-Stokes equations and the standard k-εturbulence model, the numerical simulation on internal flows through the spiral casing and stay vanes of a model hydraulic turbine applied for the Sanxia (Three-Gorge) hydro power project has been carried out by using the body-fitted coordinates, the staggered grid system and the SIMPLEC algorithm in the present work. Calculated results are presented at the design operating condition for the spiral casing and stay vanes, which give a valuable referenceto improve their design.展开更多
基金Supported by the Sustentation Plan Projects for Out-standing Young Teachers of the Ministry of Education (20011879)
文摘Complete bearing spiral case has not been applied to large power stations in China so far. The proposal of applying complete bearing spiral case necessitates an analysis of the reliability of the spiral case structure and the security of units under various working conditions. In combination with practice of a project, this paper presents a three-dimensional nonlinear finite element static analysis of the concrete using a concrete smeared crack model by means of the well-known finite element method （FEM） software ABAQUS. The stress distribution of the spiral case and reinforcing bars, the range of damages in surrounding concrete, and the displacement of structure are quantified. The computational results indicate that the embedment method ensures the structure＇s safety in strength. At the same time, the result shows that this embedment is a kind of preponderant method for embedment in aspects of economy and technique of construction, and the application of this embedment method to the hydropower station is feasible provided that some proper engineering measures are taken to constrain the width of the concrete in accord with the code＇s requirements. The paper proves the security and reliability of the structural design of spiral case in hydropower station accordingly.
文摘In consideration of the contact between the steel spiral casing and the peripheral reinforced concrete, a nonlinear analysis for the combined bearing structure of the JinPing-I preloading filling spiral case has been made with ANSYS. Contrasts of the stress of the reinforcing bars, the biggest width of the crack and the outspread section of the crack has been made with the different parameters of preloading pressure and reinforcement scheme, resulting in a reasonable preloading pressure and reinforcement scheme. This conclusion has been applied to the spiral casing of JinPing-I hydropower station.
文摘As a key backbone project in developing and harnessing the Yangtze, the Three Gorges Project (TGP) is a largest water conservancy and hydropower project in China and all the world as well. With a huge comprehensive benefit from flood control, power generation and navigation improvement, TGP, when completed, will exert a significant influence on the socio economic development across the Yangtze Basin and all China. Decisions on key technical issues concerning the construction of TGP were made on a huge number of scientific tests and verifications. The structural pattern selection of the penstock and the spiral case in the TGP power station is not only an important technical and economic issue, but also relating to the long term operation of the power station itself.
文摘The spiral casing and stay vanes are important through flow parts of a hydraulic turbine.Their internal flows have significant influence upon the hydraulic efficiency and performance of the turbine. Based on the solution of Navier-Stokes equations and the standard k-εturbulence model, the numerical simulation on internal flows through the spiral casing and stay vanes of a model hydraulic turbine applied for the Sanxia (Three-Gorge) hydro power project has been carried out by using the body-fitted coordinates, the staggered grid system and the SIMPLEC algorithm in the present work. Calculated results are presented at the design operating condition for the spiral casing and stay vanes, which give a valuable referenceto improve their design.
