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論文

論文
HUANG, Zuohua ; SHIGA, Seiichi ; UEDA, Takamasa ; JINGU, Nobuhisa ; NAKAMURA, Hisao ; ISHIMA, Tsuneaki ; OBOKATA, Tomio ; TSUE, Mitsuhiro ; KONO, Michikata
出版情報: JSME international journal. Ser. B, Fluids and thermal engineering.  45  pp.891-900,  2002-11-15.  社団法人日本機械学会
概要: application/pdf<br />Journal Article<br />A basic characteristics of compressed natural gas direct-injection (CNG DI) co mbustion was studied by using a rapid compression machine. Results show that comparing with homogeneous mixture, CNG DI has short combustion duration, high pressure rise due to combustion, and high rate of heat release, which are considered to come from the charge stratification and the gas flow generated by .the fuel injection. CNG DI can realize extremely lean combustion which reaches 0.03 equivalence ratio, φ. Combustion duration, maximum pressure rise due to combustion and combustion efficiency are found to be insensitive to the injection modes. Unburned methane showed almost the same level as that of homogeneous mixture combustion. CO increased steeply with the increase in φ when φ was greater than 0.8 due to the excessive stratification, and NO_x peak value shifted to the region of lower φ. Combustion inefficiency maintains less than 0.08 in the range of φ from 0.1 to 0.9 and increases at very low φ due to bulk quenching and at higher φ due to excessive stratification. The combustion efficiency estimated from combustion products shows good agreement with that of heat release analysis. 続きを見る
2.

論文

論文
OKAI, Keiichi ; ONO, Yutaka ; MORIUE, Osamu ; SHIBA, Seiji ; ARAKI, Mikiya ; NOMURA, Hiroshi ; SHIGA, Seiichi ; TSUE, Mitsuhiro ; KONO, Michikata
出版情報: JSME international journal. Ser. B, Fluids and thermal engineering.  44  pp.126-132,  2001-02-15.  社団法人日本機械学会
概要: application/pdf<br />Journal Article<br />Experimental investigation was conducted on two droplet-array combustion of methanol and methanol/dodecanol mixture fuels in microgravity. For methanol, effects of ambient pressure and droplet spacing were examined. Results show that the droplet lifetime decreases with increasing spacing at relatively low pressure and the droplet lifetime becomes independent of spacing at higher-subcritical and supercritical pressures. For methanol/dodecanol mixture, effects of pressure, fuel composition were investigated in terms of occurrence of disruption. Disruption of droplet during combustion was demonstrated both for single droplet and droplet pairs. 続きを見る