並列タイトル等低プラントル数流体のハーフゾーン橋中の振動流の実験的研究
タイトル（掲載誌）宇宙開発事業団技術報告: Marangoni Convection Modeling Research: Annual Report April 1, 2001-March 31, 2002 = NASDA Technical Memorandum: Marangoni Convection Modeling Research: Annual Report April 1, 2001-March 31, 2002
一般注記The first and clear experimental evidence for the transition from the steady to the oscillatory flow was presented by the non-contact temperature measurement of a molten tin surface and the surface flow visualization. The experimental study on thermocapillary convection of low Prandtl number fluid was carried out to understand transition behavior to oscillatory flow. The half-zone liquid bridge of molten tin was formed between hot and cold disks in high vacuum chamber (10(exp -5) Pa). The three radiation thermometers were used to measure the free surface temperature at a different azimuthal location at the same time. In addition, the temperature distribution at interface between liquid bridge and cold disk was measured by using very fine thermocouples to detect the transition point and to make clear the oscillation mode more precisely. It can be detected that the steady thermocapillary convection changes to oscillatory under certain condition. The effect of aspect ratio (L/r) on critical Marangoni number is investigated. The critical Marangoni number decreases with increasing the aspect number. This behavior agrees with numerical simulation done by Imaishi et al. qualitatively except for region of smaller aspect ration. The transducer with 3 x 3 LN element was made and checked its sensitivity. The sensor was verified the stability after heat treatment up to 500 C, which was same as actual thermocapillary experiment. The frequency band of oscillator was selected to get the clear echo signal. The optimal frequency was 6 to 14 MHz wide-band. The sphericity and surface roughness of Fe-Ni/SB were improved by an appropriate heat treatment technique on Ni plating process and by the organic additives to the Fe plating solution. The Fe plating rate was obtained. It was found that the thickness increased with time linearly. It could be verified that Fe and Ni plated Shirasu-balloons (Fe-Ni/SB) even in phi-0.1 mm reflected the ultrasonic.
資料番号: AA0045403006
レポート番号: NASDA-TMR-020026E
一次資料へのリンクURLhttps://jaxa.repo.nii.ac.jp/?action=repository_action_common_download&item_id=42852&item_no=1&attribute_id=31&file_no=1
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）
提供元機関・データベース宇宙航空研究開発機構 : 宇宙航空研究開発機構リポジトリ