2002 Fiscal Year Final Research Report Summary
Study on the ice formation and its removal phenomena on cooled surface
| Project/Area Number |
12650197
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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 |
Thermal engineering
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| Research Institution | Shinshu University |
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Principal Investigator |
HIRATA Tetsuo Shinshu University, Faculty of Engineering, Professor, 工学部, 教授 (40126701)
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| Project Period (FY) |
2000 – 2002
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| Keywords | Ice storage / Ice formation / Ice removal / Liquid ice / Aqueous solution / Pipe flow / Vertical tube / Cooled plate thickness |
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| Research Abstract |
In the previous study, the investigator examined an ice formation phenomenon of aqueous solution on a cooled plate, whose thermal conductivity was comparatively small. It was reported that the ice formed on a cooled plate could be removed from the plate surface due to buoyancy force acting on the ice. The present study is a basic research to apply the ice removal phenomena for practical use.
1. Study on ice removal phenomena around vertical cooled tube
An ethylene glycol aqueous solution was frozen with cooling a cooled polyvinyl chloride tube. It was found that the formed ice crystal on the cooled tube could be removed due to buoyancy force even on the vertical tube. It implies the possibility of increase of ice formation rate by installing many vertical tubes on the bottom of an ice storage vessel. It was also found that an appropriate value of the tube length exists for the onset condition of ice removal phenomena.
2. Ice removal phenomena in a cooled pipe with flowing aqueous solution
Ice formation and its removal phenomena in a cooled pipe were examined. It was found that the ice formation rate increases with decreasing flow velocity of aqueous solution. However, for very low velocity, the ice crystal was not removed from the pipe surface and an ice layer was formed over the surface.
3. Effect of cooled plate thickness on the ice removal phenomena
Ice was formed on a horizontal cooled plate with using different thickness of polyvinyl chloride plate. It was found that the thickness of 1.0-1.5mm was preferable for the ice removal phenomena.
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