Other

Mitsui Engineering and Shipbuilding Company Limited

Mitsui E&s Co., Ltd.

Kazuki Takizawa

Kazuhiro Shimizu

Kazutoshi Murata

Yasunari Mori

Shuji Ishihara

Hirofumi Himei

Kouichi Takemoto

Masaru Fujinami

Tsukasa Suzuki

An annular valve in which the shape of a sealing surface of a valve body is optimized thus suppressing the occurrence of pressure loss in gas on the periphery of the sealing surface and extending the service life of the annular valve. The annular valve comprises: a valve seatformed in a plate-like shape and including passage flow channelseach having an opening cross section formed in an arcuate shape; a receiving plateformed in a plate-like shape and having discharge flow channels, the receiving platebeing arranged to face the valve seatby way of an intermediate chamber; a valve bodyformed in an annular shape corresponding to the arcuate shape of the opening cross section of the passage flow channeland being arranged in the intermediate chamber, the valve bodybeing brought into contact with/separated from the valve seatso as to open/close the passage flow channel; and a plurality of spring memberssupported by the receiving plate, the spring memberseach biasing elastically the valve bodytoward the valve seat. A sealing surfaceof the valve bodythat faces the passage flow channelis formed in a shape where at least one of pressure loss elements with respect to gas flowing towards the valve bodyfrom the passage flow channelis eliminated.

Annular valve and valve body for annular valve

A laser beam with a wavelength capable of exciting atoms of helium in the metastable state is directed to a generated plasma, and atoms in the metastable state are excited. Absorption amount information representing the amount of laser beam absorbed is acquired, and the density of atoms of helium in the metastable state in the plasma is computed from the absorption amount. The emissions of light from helium gas in the plasma caused by transition from two different excited states to the lower level are measured, and the ratio between the intensities of the emissions is determined. The electron temperature of the produced plasma is computed from the computed density of the atoms of helium gas in the metastable state and the computed emission intensity ratio. With this, the plasma electron temperature can be computed with a relatively high accuracy irrespective of the condition of the plasma atmosphere.

Plasma electron temperature measuring method and device

Growing community of inventors

Tamano, Japan

Kazuki Takizawa