著者

大畠 英一郎 押領司 一浩

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集

巻号頁・発行日

2021

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<p>Several high energy ignitions have been proposed to improve ignition performance of diluted combustion recently. One of the major issues in the high energy ignition systems is heat generation of an ignition coil due to increase of power consumption. This study proposes a method to reduce electricity consumption by controlling time distribution of discharge energy while keeping the ignition performance. The following conclusions were obtained as results of verification with an actual engine. (1) A concept for reducing the power supply-demand difference that does not inhibit flame core growth was proposed. (2) To reduce the power supply-demand difference, an ignition coil with an additional active coil was fabricated to enable time distribution control of ignition energy. (3) By controlling the time distribution of ignition energy, both energy saving and ignitability of ignition were achieved, and the prospect of net fuel consumption improvement was obtained.</p>

著者

押領司 一浩 赤城 好彦 内勢 義文 周 玉宇 窪山 達也 森吉 泰生

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.84, no.863, pp.18-00002, 2018 (Released:2018-07-25)

参考文献数

8

被引用文献数

2

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To increase thermal efficiency of internal combustion engine, lean burn and EGR (Exhaust Gas Recirculation) system have been developed with spark ignition coils generating larger discharge current and discharge energy than current mass production coils. Several researches clarified that larger discharge current increases discharge channel extension and decreases possibility of discharge channel blow-off and possibility of misfire. However, these investigations don't mentioned effect of larger discharge current and energy on air-fuel ratio and combustion period. Then purpose of this research is to investigate relation among air-fuel ratio, combustion period and coil specification in order to clarify control factor of air-fuel ratio of lean burn. In this study, five coils having different current profiles were evaluated under 2000 rpm and 0.6 MPa NMEP (Net indicated Mean Effective Pressure) at lean mixture condition by combustion test and in-cylinder optical measurement test with research single cylinder engine. The combustion test results showed a correlation between lean limit air-fuel ratio and initial combustion period. Moreover, optical measurement test showed that initial combustion period has a correlation with discharge energy before 1st restrike and discharge channel extension rate and variation of initial combustion period under stable control condition doesn't depend on discharge current.