| Project/Area Number |
07455088
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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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 | HOKKAIDO UNSTITUTE OF TECHNOLOGY |
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Principal Investigator |
TOYODA Kuniaki INSTITUTION,DEPARTMENT,TITLE OF POSITION Hokkaido Institute of Technology, Faculty of Engineering, Professor, 工学部・機械工学科, 教授 (50048039)
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| Co-Investigator(Kenkyū-buntansha) |
SHIRAHAMA Yoshikuni INSTITUTION,DEPARTMENT,TITLE OF POSITION Hokkaido Institute of Technology, Facul, 機械工学科, 助教授 (30048061)
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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 |
¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1996: ¥1,000,000 (Direct Cost: ¥1,000,000)
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| Keywords | Cold regions / Trucks / Smoke of snow / Vortex / Spoiler / Three-dimensional perturbation / 三次元撹乱 |
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| Research Abstract |
The object of the research project is to make clear the generating mechanism of snow smoke behind trucks in cold regions in winter season, and to obtain the basic ideas to prevent the generation of snow smoke. The experimental work was carried out by using wind tunnels, and the results are as follows.
1. The evolution of large-scale vortices behind a model truck was confirmed by the visualization techniques in wind tunnel. The large-scale vortices generate the snow smoke behind trucks.
2. In order to prevent the evolution of large-scale vortices, the spoiler with three-dimensional roughness at the trailing edge was attached under the truck. The three-dimensional perturbation was very effective to break up the large-scale vortices, and the spoiler is a useful device to prevent the snow smoke.
3. The velocity fields behind the model truck on the moving belt were measured by hot-wire anemometer, and the suppression of turbulence intensity and large-scale vortices was confirmed quantitatively.
4. The above-mentioned spoiler was installed to an actual truck, and the performance of the spoiler was checked by the driving test. The result snows that the spoiler is very effective to prevent the mud adhesion to the rear surface of the truck, suggesting the suppression of the large-scale vortices behind the truck.
5. The technique to detect the three-dimensional vortical structures was developed : the complicated vortical structure in a rectangular jet was educed by the measurements of pressure fluctuations. The technique is useful to make clear the details of the vortex motions behind the spoiler.
The present work suggested the basic ideas to prevent the snow smoke behind trucks, and the further study is needed to develop the ideas.
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