A Simplified Solution Method for End-of-Term Storage Energy Maximization Model of Cascaded Hydropower Station

2020 ◽  
Vol 09 (04) ◽  
pp. 353-362
Author(s):  
新宇 武
2019 ◽  
Vol 78 ◽  
pp. 135-143
Author(s):  
Yuliang Liang ◽  
Jun-Ping Geng ◽  
Han Zhou ◽  
Tingting Fan ◽  
Xuan Wang ◽  
...  

2013 ◽  
Vol 860-863 ◽  
pp. 1565-1568
Author(s):  
Jing Yang ◽  
Li Da Zhang ◽  
Lei Lu

The normal operation of the hydropower station is seriously affected by the vibration problems. This paper is about how to analysis and improve the hydraulic vibration problem by an example of a low head Francis turbine in the southwest of China with higher head. The models was built by using UG and analysed by CFD numerical analysis software to simulate the vibration conditions with air-water two-phase flow. With the reason was found by the the result of numerical calcuate, air compensation method was put out to improve the vibration condition and the optimal volume of the compensative air was calcuated to verify the solution method.


1992 ◽  
Vol 114 (2) ◽  
pp. 231-237 ◽  
Author(s):  
C. Bagci

Presently existing strength of materials solutions for stresses in curved beams use an incorrect normal force equilibrium condition to define neutral axis location, and to reach a simplified solution, which neglects the curvature effect on stresses due to normal force. This article presents a new but a most general form of the strength of materials solution for determining tangential normal stresses in curved beams, including reductions to special cases. The neutral axis phenomenon is clarified and experimentally verified. Several numerical examples are included, some of which offer photoelastic experimental results, where results predicted by the exact elasticity solution, method of the article, Winkler’s theory, and the conventional simplified method are compared. The hook, diametrically loaded cut, and full ring applications are included. It is shown that simplified theory leads to very large errors. Results by the method offered are very reliable with small errors which are comparable with those of exact elasticity solutions. Stress and deflection analyses of curved beams with varying thicknesses of cross-sections by exact elasticity solutions are given in a separate article [6].


Author(s):  
Abbas A. Moftakhar ◽  
Grzegorz Glinka

A simplified solution method that enables the estimation of stresses and strains in high temperature components under creep conditions is presented. The solution is derived based on strain energy density considerations and is applicable to both uniaxial and multiaxial stress states. In particular, this simplified method is developed for an efficient estimation of the cyclic stress-strain history at critical locations which needed for fatigue analysis of hot sections under creep conditions where conventional finite element creep analysis becomes extremely time consuming. The input data necessary to perform this simplified solution are the stresses and strains obtained from a linear elastic analyses. If the finite element method (FEM) is used for the linear elastic analysis of components, then the simplified solution method can be programmed as a post processor file. The file uses the linear elastic FEM results and generates an approximate time-dependent analysis. Presented results illustrates the accuracy of the method by comparing with finite element creep analysis results for several hot sections under creep conditions. Also, it is shown that the computational time needed to perform this solution is far less than the conventional finite element creep analysis.


Human Ecology ◽  
2016 ◽  
pp. 3-8
Author(s):  
S. A. Ivanov ◽  
O. F. Dmitrieva ◽  
N. I. Kulmakova ◽  
Yu. O. Dimitriev

Sign in / Sign up

Export Citation Format

Share Document