1999 Fiscal Year Final Research Report Summary
Development of a Computing Code Accurate Prediction of Output and Life of Hot Dry Rock Power Generation
| Project/Area Number |
09651029
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
資源開発工学
|
|---|
| Research Institution | Yamaguchi University |
|---|
Principal Investigator |
MIZUTA Yoshiaki Yamaguchi University, Faculty of Engineering, Professor, 工学部, 教授 (20107733)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OHNISHI Yasunori Yamaguchi University, Faculty of Engineering, Research Professor, 工学部, 助手 (00274184)
ISHIDA Tsuyoshi Yamaguchi University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (10232307)
KURIYAMA Ken Yamaguchi University, Faculty of Engineering, Professor, 工学部, 教授 (10116717)
|
|---|
| Project Period (FY) |
1997 – 1999
|
| Keywords | Fictitious Stress Method / Analytical Integration / Division into elements / Displacement Discontinuity Method / Crack Tip Element / Non-Steady Heat Conduction / Flow in Fracture / Heat Extraction |
|---|
| Research Abstract |
The investigators almost have completed main frame of the computing system for accurate prediction of output and life of Hot Dry Rock power generation. The computing system combine the sub-systems which are to analyze : (1) non-steady heat conduction in the infinite medium under thermal boundary condition and thermal elasticity induced by temperature gradient, (2) aperture distribution of the fracture created by hydrofracturing and deformation of rock around the fracture under mechanical boundary condition, (3) stress intensity factor at fracture tip and fracture extension due to aperture expansion induced by interaction of rock stress, fluid pressure in the fracture and thermal elasticity, and (4) velocity distribution of non-steady fluid flow in the fracture and heat transfer from rock to fluid flow.
They already completed the sub-systems, (1)〜(3) and the fruits with respect to (1) and (2) were already reported in the journals. The results of (3) will be reported at two international congress held in 2000. A part of (4), that is, development of the sub-system to calculate heat transfer is not completed but the basis of it will soon be completed.
The research results obtained in FY 1999 are as follows :
1) In the past, division of the boundary into elements such that the center of gravity of some element lay on the prolongations of three sides of any other triangular element, was not permitted. In the procedure developed in this study, strict analytical integration for such case can be done. Furthermore, the expressions of analytical integrals become simple and so, computation can be fast and accurate.
2) Strict analytical integration for crack-tip element whose displacement discontinuity distribution is square root shape, was put into operation and so, precise calculation of stress intensity factor at fracture tip can be done.
|
