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Acta Mechanica Sinica

, Volume 20, Issue 4, pp 374–382 | Cite as

Underwater acoustics and cavitating flow of water entry

  • Shi Honghui
  • Kume Makoto
Article

Abstract

The fluid mechanics of water entry is studied through investigating the underwater acoustics and the supercavitation. Underwater acoustic signals in water entry are extensively measured at about 30 different positions by using a PVDF needle hydrophone. From the measurements we obtain (1) the primary shock wave caused by the impact of the blunt body on free surface; (2) the vapor pressure inside the cavity; (3) the secondary shock wave caused by pulling away of the cavity from free surface; and so on. The supercavitation induced by the blunt body is observed by using a digital high-speed video camera as well as the single shot photography. The periodic and 3 dimensional motion of the supercavitation is revealed. The experiment is carried out at room temperature.

Key Words

water entry underwater acoustics supercavitation PVDF hydrophone high-speed photography 

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Copyright information

© Chinese Society of Theoretical and Applied Mechanics 2004

Authors and Affiliations

  • Shi Honghui
    • 1
    • 2
  • Kume Makoto
    • 3
  1. 1.State Key Laboratory of Nonlinear Mechanics, Institute of MechanicsChinese Academy of SciencesBeijingChina
  2. 2.College of Mechanical Engineering and Automatic ControlZhejiang University of SciencesHangzhouChina
  3. 3.Department of Mechanical EngineeringNagoya Institute of TechnologyNagoyaJapan

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