1999 Fiscal Year Final Research Report Summary
Development of the software for the analysis of the disaster of an earthquake using the approach of the computational fluid dynamics
| Project/Area Number |
09558049
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 展開研究 |
|---|
| Research Field |
Natural disaster science
|
|---|
| Research Institution | Ochanomizu University |
|---|
Principal Investigator |
KAWARURA Tetuya Ochanomizu University, Graduate School of Humanities and Sciences, Professor, 人間文化研究科, 教授 (40143383)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OSHIMA Yoshitaka Maeda Kensetsu Inc., Section of Construction, chief, 土木設計部, 課長(研究職)
IWATSU Reima Tokyo Denki University, Department of Mechanical Engineering, Associate Professor, 工学部, 助教授
SATO Hiroshi Ochanomizu University, Graduate School of Humanities and Sciences, Professor, 人間文化研究科, 教授 (10017197)
|
|---|
| Project Period (FY) |
1997 – 1999
|
| Keywords | Earthquake / Computer Software / Propagation of Seismic Wave / Fire Tornado / Low Mach Number Approximation / Vortex Breakdown / Free Surface / Numerical Simulation |
|---|
| Research Abstract |
There are many investigations concerning to the disaster of an earthquake. However there are few studies which use CFD (Computational Fluid Dynamics) approach except for those of the tidal wave. In the present research, we focus on this point and try to apply CFD method. The present research consists of two parts. One is the prediction of the flow field caused by the big fire due to an earthquake and the other is analysis of the propagation of the seismic wave and make clear the mechanism of the unexpected amplification of the wave.
For the study of the flow induced by the big fire, two numerical methods are developed and verified. By using these methods, it is found that a fire tornado is actually generated by Coriolis force, moving around and finally breaks down and these processes are repeated temporary. The effect of the stratification on the formation of the tornado is also investigated. The flow visualization is also focused in this study and it is found that the volume rendering technique is suitable for analizing the results.
In general, an alluvium lays on a hard base rock. This means that it is possible to regard this propagation problem as that of the water wave in a container, i.e. it is possible to consider the alluvium as the water and the base rock as the container. By using this analogy, the propagation of the water wave on the free surface is simulated instead of the propagation of seismic waves. The water wave is produced by the deformation of a container in time. Using the methods developed in this study, the water waves in the two typical shape of the container which is similar to the Hanshin and San Francisco area are simulated and it is found that the amplitude of the wave becomes large at the special positions which are peculiar to the shape of the container due to the complex reflection and interference.
|
