AN INVESTIGATION TO IMPROVE THE SWATH WETDECK SLAM RATE PREDICTION METHOD

A report is given of an analysis made of data from recent SWATH seakeeping tests in an effort to improve the method of predicting the frequency of occurrence of slams on the cross structure of SWATHs. An investigation of the relationships among impact pressure, relative velocity and relative impact angle between the free surface and the wetdeck at the point of impact was undertaken and found to be inconclusive. It is recommended that future SWATH models include dynamically scaled struts in order to define through acceleration and vibration criteria when a wave impact should be considered a slam. Results of this analysis reveal that impacts of a significant magnitude start to occur when relative velocity at station 4.67 exceeds five feet per second for the 279 foot SWATH T-AGOS 23.

• Supplemental Notes:
  • Report; DTIC distribution restrictions apply
• Corporate Authors:

  David Taylor Naval Ship R&D Center

  Bethesda, MD  United States  20084

  Naval Sea Systems Command

  , ZZ N/A   
• Authors:
  • Broussard, J R
  • Lewis, R R
  • Lesko, J J
• Publication Date: 1989-11

Media Info

• Features: References;
• Pagination: 45 p.

Subject/Index Terms

• TRT Terms: Decks (Ships); Forecasting; Impact loads; Slamming; SWATH ships
• Old TRIS Terms: Deck wetness; Rates (Per time); Whipping
• Subject Areas: Marine Transportation; Planning and Forecasting; Vehicles and Equipment;

Filing Info

• Accession Number: 00659929
• Record Type: Publication
• Source Agency: Maritime Technical Information Facility
• Report/Paper Numbers: DTRC/SHD-1294-12
• Files: TRIS
• Created Date: Jul 21 1994 12:00AM