2001 Fiscal Year Final Research Report Summary
Study on the Development of Automatc Line-Heating System
| Project/Area Number |
10555340
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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 | 展開研究 |
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| Research Field |
船舶工学
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| Research Institution | Osaka University |
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Principal Investigator |
OSAWA Naoki Osaka Univ., Grad. School of Eng., Assoc. Professor, 大学院・工学研究科, 助教授 (90252585)
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| Co-Investigator(Kenkyū-buntansha) |
MURAKAWA Hidekazu Osaka Univ., J. W. R. I., Professor, 接合科学研究所, 教授 (60166270)
HASHIMOTO Kiyoshi Osaka Univ., Grad. School of Eng., Res. Assistant, 大学院・工学研究科, 助手 (50183554)
TOMITA Yasumitsu Osaka Univ., Grad. School of Eng., Professor, 大学院・工学研究科, 助教授 (30029251)
DEGUCHI Yoshikazu Mitsubishi Heavy Industries, Nagasaki Research, 長崎研究所, 主任
NAKACHO Keiji Osaka Univ., J. W. R. I., Professor, 接合科学研究所, 助教授 (10112070)
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| Project Period (FY) |
1998 – 2000
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| Keywords | Line-heating / Manufacturing practice / Heat transfer / Finite different method / L.I.F. measurement / Impinging jet |
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| Research Abstract |
In order to automate Line-heating process, an estimation method of heat transfer between flame and plate is developed. The major results obtained are as follows.
1) It is found that the temperature distribution near the plate can be estimated by calculating the heat flow of non-combustion impinging-jet in place of the combustion flame. In this approach, it is needed to give the temperature and velocity of the Virtual non-combustion gas at the nozzle exit as the calculation Conditions. For 2-dimensional gas flame, close agreement, between observed and calculated temperature near the plate surface was obtained when the highest temperature within the flame and the velocity of gas mixture at the upstream side of the nozzle was employed as the temperature and velocity of the virtual gas at the exit.
2) It is found that the local heat transfer coefficient can evaluated by the logarithmic law (wall law). Appropriateness of this formulation was proved experimentally for 2-dimensional gas flame.
3) The transient 3-dimensional temperature distribution within the gas flame during line heating is measured in detail by a high performance L.I.F. measurement system. It has been found that the relative distribution of gas temperature around the torch is almost the same as that in spot heating. It has also been found that this relative distribution is almost unchanged regardless of the temperature increase in the steel plate. These results lead us to a new hypothesis that the relative distributions of gas temperature and local heat transfer coefficient around the torch remain unchanged and they are almost the same as those in spot heating during line heating process. A new method of heat input estimation for line heating process based on this hypothesis has been propounded.
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