Research on ocean turbulence process from LES simulation and turbulence microstructure observation

2013 Fiscal Year Final Research Report

• Project/Area Number: 22340140
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Kyushu University
• Principal Investigator: WAKATA YOSHINOBU 九州大学, 応用力学研究所, 教授 (90201871)
• Co-Investigator(Kenkyū-buntansha): YOON Jong-hwan 九州大学, 応用力学研究所, 教授 (80111459) ; YOSHIKAWA Yutaka 京都大学, 理学研究科, 准教授 (40346854) ; ENDHO Takahiro 九州大学, 応用力学研究所, 学術研究員 (10422362) ; YOSHIMURA Hiroshi 長崎大学, 水産学部, 教授 (40108353)
• Co-Investigator(Renkei-kenkyūsha): AOSHIMA Takashi 長崎大学, 水産学部, 准教授 (40244040) ; YAMAWAKI Nobuhiro 長崎大学, 水産学部, 准教授 (50295101) ; KINOSHITA Tsukasa 長崎大学, 水産学部, 助教 (40452859) ; UCHIDA Jun 長崎大学, 水産学部, 助教 (30548342) ; MASUDA Akira 九州大学, 応用力学研究所, 学術研究員 (60091401) ; MATSUNO Takeshi 九州大学, 応用力学研究所, 教授 (10209588) ; ICHIKAWA Kaoru 九州大学, 応用力学研究所, 准教授 (40263959)
• Project Period (FY): 2010-04-01 – 2014-03-31
• Keywords: 海洋乱流 / 潮汐 / ADCP / 乱流微細構造プロファイラー / LES / レイノルズ応力 / エネルギー散逸率 / 東シナ海

Research Abstract

The present study developed a new observation method of turbulence and carried out the observation in the East China Sea, and concurrently those observational results were simulated and analyzed by using the parallel large eddy simulation model (LES). The energy dissipation rates were obtained from the turbulence microstructure profiler and tidal currents were from 5 beam acoustic Doppler current profiler (ADCP) in 2011. Furthermore, the Reynolds stresses were observed using the improved ADCP with high frequency beam in 2013, and the semi-diurnal change of Reynolds stress owing to the tidally oscillated flow was found. LES simulation succeeded to reproduce the main properties of tidal flows and the turbulence from the initial condition and the external forcing estimated from the observational data in 2011.

Research Products

• [Journal Article] Some properties of tidal currents estimated analytical and LES simulation studies (2013)
  • Author(s): Wakata Y
  • Journal Title: Journal of Oceanography Volume: 69 Pages: 237-751
  • DOI: 10.1007/s10872-013-0204-6
  • Peer Reviewed
• [Journal Article] Tidal and low-frequency currents along the CL line (31 deg 45 min N) over the East China Sea Shelf (2012)
  • Author(s): Yoshikawa Y
  • Journal Title: Continental Shelf Research Pages: 41-53
  • DOI: 10.1016/j.csr.2012.10.007
  • Peer Reviewed
• [Journal Article] Dependence of seafloor boundary layer thickness on the overlying flow direction : a large eddy simulation study (2011)
  • Author(s): Wakata Y
  • Journal Title: Journal of Oceanography Volume: 67 Pages: 667-673
  • DOI: 10.1007/s10872-011-0068-6
  • Peer Reviewed
• [Journal Article] Turbulent bottom Ekman boundary layer measured over a continental shelf (2010)
  • Author(s): Yoshikawa Y, T. Endoh, T. Matsuno, T. Wagawa, E. Tsutsumi, H. Yoshimura and Y. Morii
  • Journal Title: Geophysical Research Letters
  • DOI: 10.1029/2010GL044156
  • Peer Reviewed
• [Presentation] Tidal oscillations in the east China Sea simulated by LES (2014)
  • Author(s): Wakata,Y., T. Endoh, Y. Yoshikawa
  • Organizer: 2014 Ocean Sciences Meeting
  • Place of Presentation: Hawaii, USA
  • Year and Date: 2014-02-27
• [Presentation] Estimating Reynolds stress from ADCP measurements in the bottom boundary layer over the continental shelf of the East China Sea (2014)
  • Author(s): Endoh, T., Y. Yoshikawa, T. Matsuno, K. Yufu and Y. Wakata
  • Organizer: 2014 Ocean Sciences Meeting
  • Place of Presentation: Hawaii, USA
  • Year and Date: 2014-02-26
• [Presentation] Measurements of vertical turbulent fluxes of nitrate and chlorophyll-a into the surface mixed layer (2011)
  • Author(s): Endoh, T., T. Matsuno, Y.Yoshikawa, and J. Ishizaka
  • Organizer: The 5th international symposium on the East Asian environmental problems
  • Place of Presentation: Fukuoka, Japan
  • Year and Date: 2011-11-14
• [Presentation] Large eddy simulation of benthic boundary layer under a tidally oscillating flow (2011)
  • Author(s): Wakata, Y
  • Organizer: International Union of Geodesy and Geophysics (IUGG) General Assembly
  • Place of Presentation: Melbourne, Australia
  • Year and Date: 2011-06-30
• [Presentation] Fine-scale vertical shear of horizontal velocity estimated using an accelerometer mounted on the TurboMAP (2011)
  • Author(s): Endoh,T., T.Matsuno, and Y. Yoshikawa
  • Organizer: Workshop on the vertical processes in the shelf region of the East China Sea
  • Place of Presentation: Fukuoka. Japan
  • Year and Date: 2011-02-22
• [Book] ENSO の理論 (2013)
  • Author(s): 和方吉信
  • Total Pages: 21-34
  • Publisher: 日本気象学会