2024-03-29T13:28:20Z
https://u-ryukyu.repo.nii.ac.jp/oai
oai:u-ryukyu.repo.nii.ac.jp:02006984
2022-10-31T03:12:45Z
1642837622505:1642837994858:1642837999752
1642838403551:1642838406414
Observation on the Vortex Rings
Igei, Ryokan
open access
Observation was made on the vortex rings produced by ejecting dyed water into transparent water from a circular orifice of a glass tube of 0.75 cm in diameter. The translational velocity of the ring at the eight-diameter distance (6.0 cm) was used for the calculation of the Reynolds number. First, the graphs of the translational velocity vs. distance traveled by the ring plotted on semi -log paper indicate that in the later stage of the motion there exists an exponential type of dependence of the velocity on the distance, v" - exp ( - k y), the value of k depending on the Reynolds number, with k decreasing as the Reynolds number increases. Next, from the relation between the velocity and time elapsed plotted on log-log paper, it is found that when the power law approximation, v - t ^<-b>, is adopted for the later part of the motion, the value of bapproximately equals to 1 for each ring regardless the Reynolds number. Finally, our result suggeststs a linear relationship between the maximum distance traveled by the ring before its breakdown and the Reynolds number.
紀要論文
琉球大学理工学部
Science and Engineering Division, University of the Ryukyus
1975-09-01
eng
departmental bulletin paper
NA
http://hdl.handle.net/20.500.12000/23529
http://hdl.handle.net/20.500.12000/23529
https://u-ryukyu.repo.nii.ac.jp/records/2006984
AN0025080X
琉球大学理工学部紀要. 理学編
Bulletin of Science & Engineering Division, University of Ryukyus. Mathematics & natural sciences
20
15
22
https://u-ryukyu.repo.nii.ac.jp/record/2006984/files/No20p015.pdf