Accession Number:

ADA099704

Title:

Ship Response Sensitivity to Forecast and Measured Wave Spectra

Descriptive Note:

Final rept.

Corporate Author:

DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD SHIP PERFORMANCE DEPT

Personal Author(s):

Report Date:

1980-12-01

Pagination or Media Count:

95.0

Abstract:

This study presents some preliminary investigations on calculating ship response by using the Spectral Ocean Wave Model SOWM for wave inputs to SMP80, the Navys Standard Ship Motion Prediction Program. This technique could be a valuable tool for design and operations by providing a measure of ship response in specific conditions and over requested routes. The ship used to develop the motion responses was the Dutch oceanographic research ship HNLMS TYDEMAN, which is relatively short and beamy. Comparisons of predicted and measured ship response are given in the frequency domain. Significant values derived from spectra are also compared. The quantity of measured data for correlation is limited but agreement of the SOWM forecast waves with measured waves is not completely satisfactory. The ability to predict realistic ship response is also tenuous for the ship HNLMS TYDEMAN. The geometry of that ship is near the limits of that permitted by the ship motion strip theory encapsulated in SMP80. For pitch and heave motions, the forecast response spectra show inadequate agreement with measured response spectra and could provide unreliable indicators of ship performance. Roll, which is a narrow- banded process, is fairly insensitive to the correlation between the forecast and measured waves in the cases examined. For those cases, peak frequency always matched between forecast and measured roll responses. Samples wave forecast and measurement comparisons are also provided for a routine North Atlantic transit of the Dutch container ship MV HOLLANDIA. Author

Subject Categories:

  • Physical and Dynamic Oceanography
  • Marine Engineering
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE