Full Content is available to subscribers

Subscribe/Learn More  >

Experimental Research on Flow Induced Oscillations in Moonpool Encountered Through Waves

[+] Author Affiliations
Zhuang Kang, Xiongliang Yao, Sadiq Salman

Harbin Engineering University, Harbin, Heilongjiang, China

Paper No. OMAE2007-29370, pp. 433-442; 10 pages
  • ASME 2007 26th International Conference on Offshore Mechanics and Arctic Engineering
  • Volume 1: Offshore Technology; Special Symposium on Ocean Measurements and Their Influence on Design
  • San Diego, California, USA, June 10–15, 2007
  • Conference Sponsors: Ocean, Offshore and Arctic Engineering Division
  • ISBN: 0-7918-4267-3 | eISBN: 0-7918-3799-8
  • Copyright © 2007 by ASME


Model experiments in this paper explains the response of the moonpool encountered through waves at different wave heights, time periods and attack angles, which reflect close to real situation at sea for ships equipped with moonpool. EMD method is used to have a meaningful data collected through hydrophone, pressure sensors, acceleration sensor and wave height meter. Results show that fluid natural oscillating frequency remains constant at 0.7 Hz in calm water with forward model speed condition (Fr = 0.26∼1.3), while by increasing the time period, wave height or both; it fluctuates between 0.6 Hz∼0.9 Hz. The fluid inside the moonpool faces internal sloshing, resulting in transverse breaking waves that are added to the vertical motions. Sloshing motion in the moonpool couples with the piston mode due to which results of calm water with forward speed, and combined waves and flow condition are quite different. Square shaped moonpool at different attack angles and circular shaped moonpool are also discussed for fluctuating pressure level (dB) at increasing time period and wave height. Moreover, Oscillation pressure results at only-wave condition and wave and flow condition together are represented by using frequency ratio between ‘oscillation pressure frequency’ and ‘sloshing natural frequency’ with varying ‘KC ’ number. KC varies from 4.16 to 5.67 at 1-sec time period having frequency ratio f/fo of 1. Once time period increases to 2-sec, KC becomes around 22.69 at same frequency ratio. Dynamic magnification due to waves and flow combined situation may cause slamming on diving bells or ROV that are launched, green water over the edge of the moonpool which can be dangerous for the crew, or can increase drastically the resistance of the vessel in transit conditions therefore, this experimental research gives very important factors and results for designing moonpool; we believe that this paper has a significant contribution in the permanent literature.

Copyright © 2007 by ASME



Interactive Graphics


Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In