| Project/Area Number |
07650268
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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 | NIHON UNIVERSITY |
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Principal Investigator |
UJIIE Yasusige NIHON UNIVERSITY,COLLEGE OF INDUSTRIAL TECHNOLOGY,PROFESSOR, 生産工学部, 教授 (20060197)
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| Co-Investigator(Kenkyū-buntansha) |
NOMURA Hiroshi NIHON UNIVERSITY,COLLEGE OF INDUSTRIAL TECHNOLOGY,ASSISTANT PROFESSOR, 生産工学部, 講師 (30246847)
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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 |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1996: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1995: ¥1,800,000 (Direct Cost: ¥1,800,000)
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| Keywords | Spark Ignitinn / Combustible Mixture / Free Radical / Spark Energy / Spectroscopic Analysis / Gasoline Engine / Spark Kernel / 内燃機関 / 予混合燃焼 / 乱流場 / 火花電極 / 熱損失 |
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| Research Abstract |
Study on OH radical formation at the beginning of spark ignition has been performed experimentally. The purpose is to declare the effect of spark discharge on the initial formation of OH radical and the role of OH radical in the initiation of combustion chemical reaction. A double monochromator and an ultra-high-speed camera with a band pass filter were employed to observe the behavior of OH radical by its self-emission (306nm). The growth of a flame kernel was observed by schlieren photography with the ultra-high-speed camara. Propane-air premixture was used as a combustible gas : The concentration of propane was 4.7 vol% for all tests. Capacitance spark was employed to ignite premixtures. Electrodes were made of stainless steel and their diameter were 0.5 mm. Spark gap was adjusted to be 0.8 mm. The energy of spark was varied from 15 to 80 mJ.
The behavior of OH radical was observed successfully from 1.2 to 40 mus after a spark discharge. The concentration of OH radical is high just after a spark discharge and decreases gradually from 10 mus. As spark energy increases, amount of OH radical formed at the beginning of spark ignition increases and growth rate of a flame kernel increases. It was found that, when the spark energy is large, there is little OH radical in the initial flame kernel and it exists near the edge of the initial flame kernel. From schlieren photographs of flame kernels, it was observed that high temperature region in the center of the flame kernel remains longer as spark energy increases. The life time of the high temperature region is longer than double the spark duration. It is suggested that this high temperature region accelerates the formation of OH radical at the boundary between the high temperature region and the propane-air premixture.
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