title: Oscillation of a rotating levitated droplet: Analysis with a mechanical model.
abstract: A droplet of millimeter-to-centimeter scale can exhibit electrostatic levitation, and such levitated droplets can be used for the measurement of the surface tension of the liquids by observing the characteristic frequency of oscillatory deformation. In the present study, a simple mechanical model is proposed by considering a single mode of oscillation in the ellipsoidal deformation of a levitated rotating droplet. By measuring the oscillation frequency with respect to the rotational speed and oscillation amplitude, it is expected that the accuracy of the surface tension measurement could be improved. Using the proposed model, the dependences of the characteristic frequency of oscillatory deformation and the averaged aspect ratio are calculated with respect to the rotational angular velocity of a rotating droplet. These dependences are found to be consistent with the experimental observations.
authors.affiliation: Department of Physics, Graduate School of Science, Chiba University, Chiba 263-8522, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kitahata
authors.affiliation: Graduate School of System and Information Engineering, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Rui
authors.initials: R
authors.lastname: Tanaka
authors.affiliation: Department of Physics, Graduate School of Science, Chiba University, Chiba 263-8522, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Koyano
authors.affiliation: Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Tsukuba, Ibaraki 305-8505, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Matsumoto
authors.affiliation: Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo 153-8904, Japan.
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Nishinari
authors.affiliation: Research Institute of Nuclear Engineering, University of Fukui, Tsuruga, Fukui 914-0055, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Faculty of Engineering, Kogakuin University, Shinjuku-ku, Tokyo 163-8677, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Hasegawa
authors.affiliation: Graduate School of System and Information Engineering, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kanagawa
authors.affiliation: Graduate School of System and Information Engineering, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Kaneko
authors.affiliation: Graduate School of System and Information Engineering, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Abe