| Project/Area Number |
07650205
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Fluid engineering
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| Research Institution | Osaka University |
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Principal Investigator |
TANAKA Toshitsugu Osaka University, Faculty of Engineering, Assoc.Professor, 工学部, 助教授 (90171777)
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| Co-Investigator(Kenkyū-buntansha) |
KAWAGUCHI Toshihiro Osaka University, Faculty of Engineering, Research Assoc., 工学部, 助手 (80234045)
TSUJI Yutaka Osaka University, Faculty of Engineering, Professor, 工学部, 教授 (10029233)
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| Project Period (FY) |
1995 – 1996
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| Project Status |
Completed (Fiscal Year 1996)
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| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1996: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1995: ¥1,500,000 (Direct Cost: ¥1,500,000)
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| Keywords | Multiphase Flow / Gas-Solid Flow / Turbulence / Numerical simulation / LES / 数値スミュレーション |
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| Research Abstract |
1.LES of downward gas-solid flows in a vertical channel
Numerical smuations with two-way couping were performed for downward particle laden tutbulent flows in a verticul channel. Fluid motion was culculated by using LES with the same models as in single phase flows and the motin of individual particles by the Lagrangian method. Particleparticle collisin was taken into considertion.
The present simulation showed that fluid turbulence is modified by particles but quantitatively did not get a good agreement with the measurement.
It was found that the effects of particle-particle collisinon on particle diffusion is large even at low ppaticle volume fraction of the order O (10-4), and that the predicted paticle fluctuation velocity in transverse direction is as two times as that without particle-particle collisimon.
the predicted particle fluctuation velocies agreed well with the experiment by Kulick et al. (1994). By visualizing the calculated flow field the relation between the particle distribution and the streak structure was studied. It was found that particles tend to concentrate to the low speed streaks.
2.Structure of paticle cluster
The results of LES shown that particles tend to form particle clauds caused by the streak structure. It is known that particles form dense clusters and affect turbulent structure largely when particle concentration increases. The structure of particle cluster is also simulated numerically. The characteristic structures both in two-dimensional and three dimensional fields were found. It was found that the spatial scale of cluster increases with increasing particle diameter.
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