1 0 0 0 OA レーザーブレイクダウン支援長距離火花放電による広域点火に関する研究
火花点火ガソリンエンジンの希薄燃焼限界を向上させる新しい広域点火法を提案した。レーザーブレイクダウンと高電圧印加を組み合わせた長距離放電点火LBALDI (Laser Breakdown Assisted Long-distance Discharge Ignition) の基礎特性明確化と有効性実証を目的としている。レーザーと高電圧印加の角度は90°付近が最も放電距離が長くなる。定容容器を用いて燃料依存性を調査しルイス数1以上の条件にて有効な点火法であることが分かった。急速圧縮装置を用いてエンジンに近い条件の高圧場においても長距離放電可能なLBALDIの有効性を実証し、目標を達成した。
- 著者
- 秋濱 一弘
- 出版者
- 一般社団法人 日本燃焼学会
- 雑誌
- 日本燃焼学会誌 (ISSN:13471864)
- 巻号頁・発行日
- vol.59, no.187, pp.49-54, 2017 (Released:2018-02-15)
- 参考文献数
- 21
- 被引用文献数
- 6
Gasoline vehicles, particularly, Gasoline Direct Injection (GDI) vehicles were subjected to regulations of PM (Particulate Matter) emissions because of the sales increase of GDI vehicles in the market. In this article, the emissions standards of PM for gasoline vehicles in Japan, EU and USA (EPA) are reviewed, and the latest regulatory trend are compared. The outline of PM generation in a GDI engine are explained as the fundamental information. In cold-fast-idle condition, for example, PM emissions in GDI engine originate from the wall fuel films produced by the fuel jet. The reported chemical compositions of exhaust PM are summarized. The major component is found to be Elemental Carbon (EC). Finally, the need for the modeling of PM generation is discussed for the numerical simulation in order to investigate the GDI engine with lower PM emission in the future.
1 0 0 0 OA レーザ超音波による溶接状態の可視化手法の検討
- 著者
- 木下 雅夫 蝦名 正輝 大澤 正敬 日比野 良一 門浦 弘明 秋濱 一弘
- 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C編 (ISSN:18848354)
- 巻号頁・発行日
- vol.78, no.792, pp.2824-2836, 2012 (Released:2012-08-25)
- 参考文献数
- 23
- 被引用文献数
- 5
This paper discusses a research on 2-dimensionl visualization of a spot weld piece using laser-ultrasonic technique. This laser-ultrasonic apparatus can scan a surface on a weld piece, and get ultrasonic longitudinal signals on several hundred measurement points per 10mm order. We analyzed these signals by Frequency Response Characteristic from 10MHz to 100MHz, and showed that the ultrasonic attenuation was related to the gain, and the ultrasonic propagation velocity was related to the phase, for frequency domain spectrum. At result, it was appeared that the gain of nugget parts was less than the gain of parents, and the phase of HAZ was latter than the phase of parents and nuggets. From these results, we made maps on frequency domain spectrum, and could realize to visualize the parent and the nugget, the HAZ on a weld piece. In addition, using Electron Back Scatter Diffraction, it was shown that the gain was effected by the crystal diameters, the phase was effected by the crystal directions.