著者
Kiyan Tsuyoshi Takade Maya Namihira Takao Hara Masanori Sasaki Mitsuru Goto Motonobu Akiyama Hidenori キヤン ツヨシ タカデ マヤ ナミヒラ タカオ ハラ マサノリ ササキ ミツル ゴトウ モトノブ アキヤマ ヒデノリ 喜屋武 毅 高出 麻耶 浪平 隆男 佐々木 満 後藤 元信 秋山 秀典
出版者
Institute of Electrical and Electronics Engineers
雑誌
IEEE transactions on plasma science
巻号頁・発行日
vol.36, no.3, pp.821-827, 2008-06
被引用文献数
4 33

This paper deals with the effect of the polarity and gap geometry on dc breakdown voltage characteristics of a pointto-plane gap in supercritical carbon dioxide (SC CO2) that is required to design a plasma reactor. In the experiments, the gap width d and the curvature radius of the point tip r were changed in the range of 80 to 300 μm and 50 to 170 μm respectively,and the CO2 state was controlled within the gas, liquid, and SC phases. The experimental results showed that a remarkable polarity effect appeared under certain gap conditions. As a result, it was found that negative polarity and a higher stressed electrode are desired conditions for the dc plasma reactor since an active corona supplying rich chemical radicals appears in SC CO2 under such conditions.
著者
Namihira Takao Tsukamoto Shunsuke Wang Douyan Hori Hideo Katsuki Sunao Hackam Reuben Akiyama Hidenori Shimizu Masaru Yokoyama Kenichi ナミヒラ タカオ ツカモト シュンスケ ホリ ヒデオ カツキ スナオ アキヤマ ヒデノリ シミズ マサル ヨコヤマ ケンイチ オウ トエン 浪平 隆男 勝木 淳 秋山 秀典 王 斗艶
出版者
Institute of Electrical and Electronics Engineers
雑誌
IEEE TRANSACTIONS ON PLASMA SCIENCE
巻号頁・発行日
vol.29, no.4, pp.592-598, 2001-08
被引用文献数
8 49

A short duration of 100-ns pulsed power has been used to remove nitric oxide (NO) in a mixture of nitrogen, oxygen, water vapor, and NO, simulating flue gases from a power station. The effects of the gas flow rate, the reactor length, and the pulse repetition rate on the percentage of NO removal and its energy efficiency are reported. The percentage of NO removal at a fixed gas flow rate increased with increasing pulse repetition rate due to the increased energy into the discharge. At a fixed pulse rate, the removal of NO increased with decreasing gas flow rate due to the increased residence time of the gas in the discharge reactor, thus facilitating the creation of increased radicals of O and N which then decreased NO. The energy removal efficiency of NO (in mol/kWh) decreased with increasing gas flow rate and increasing removal ratio of NO. The removal of NO increased with increasing energy density (J/I) input into the discharge at different reactor length.
著者
Wang Douyan Jikuya Manabu Yoshida Seishi Namihira Takao Katsuki Sunao Akiyama Hidenori オウ トエン ジクヤ マナブ ヨシダ セイシ ナミヒラ タカオ カツキ スナオ アキヤマ ヒデノリ 王 斗艶 軸屋 学 吉田 政史 浪平 隆男 勝木 淳 秋山 秀典
出版者
Institute of Electrical and Electronics Engineers
雑誌
IEEE transactions on plasma science
巻号頁・発行日
vol.35, no.4, pp.1098-1103, 2007-08
被引用文献数
6 81

A Blumlein generator that has a pulsewidth of 100 nswas used to investigate the process of streamer discharge propagationin a coaxial cylindrical reactor using a streak camera. Bothpositive and negative polarities of the streamer discharges wereperformed in air at atmospheric pressure. The results showed thatthe primary and secondary streamers propagated with increasingvelocity from the central rod to the outer cylinder electrode inboth positive and negative polarities of applied voltages to the rodelectrode. The propagation velocity of the streamer heads was inthe range of 0.8–1.2 mm/ns for a positive peak applied voltage inthe range of 43–60 kV and 0.6 mm/ns for a negative peak appliedvoltage of−93 kV, respectively. The electric field at streamer onsetwas calculated to be 12 and 20 MV/m for positive and negativeapplied voltages, respectively