@techreport{oai:jaxa.repo.nii.ac.jp:00041370,
 author = {奥出, 宗重 and 大蔵, 信之 and Okude, Muneshige and Okura, Nobuyuki},
 month = {Dec},
 note = {27-28 Sept. 1999 (25th). 27-28 Mar. 2000 (26th), 27-28 Sept. 1999 (25th). 27-28 Mar. 2000 (26th), スモーク可視化手法を使って変形過程における渦輪の構造を検討した。高速ビデオカメラを用いて渦輪軸に対して垂直な断面の流れ模様の写真を連続的に撮影した。コンピュータグラフィックス手法を使ってこれらの写真を構成して渦輪の立体画像を得た。渦輪発生直後、立体画像はドーナツ状の形状を現した。渦輪が下流に移動するにつれて立体画像の表面に規則的に円周方向の変形が現れ、立体画像は多角形に成長した。立体画像の円周面内周部の変形は表面外周部の変形よりも大きい。最終段階、すなわち渦輪の崩壊直前では、一対の環が渦輪の渦核を取り巻くように見える。一対の環は渦核とは結合しない。一対の環は遠心力不安定のため発生した小さな一対の渦輪で構成されている。, The structure of a vortex ring in deformation process was investigated by means of smoke visualization technique. The photographs of the flow pattern of a section perpendicular to the axis of a vortex ring were taken continuously with a high-speed video camera. The solid picture of a vortex ring was obtained by constructing these photographs with a computer graphics tool. Just after generating a vortex ring, the solid picture displayed a shape like the doughnut. The circumferential distortion appeared regularly on the surface of a solid picture as the vortex ring traveled downstream and the solid picture grew into the polygon. The distortion of the inner side on the circumferential surface of the solid picture was larger than that of the outer side on the surface. At final stage, i.e., just before collapse of the vortex ring, it seemed that a pair of rings might enclose the vortex core of vortex ring. These pairs of rings were not combined with the vortex core. The pair of rings may be constructed of a small pair of vortex ring, which are generated due to the centrifugal instability., 資料番号: AA0028636010, レポート番号: NAL SP-47},
 title = {渦輪の変形過程における構造},
 year = {2000}
}