Calculation of Far Field Radiation and Diffraction Wave Patterns Using the Kochin Function Approach for a Series of Ship Hulls
Abstract
The report presents the calculation procedure and numerical results for the far field radiation and diffraction wave patterns around a ship at zero forward speed. The calculation procedure uses the strip theory Ship Motions Program to obtain the motion transfer coefficients and singularity strengths in the form of the integrated Kochin functions. These results are then combined with an asymptotic expression for the far field wave elevation due to a three- dimensional oscillating source to obtain the ship wave patterns. The wave patterns are calculated for a series of six ships, including a strut like hull, excited by ambient waves representative of Sea States 2,4,6, and 8. The radiation waves are calculated for all six modes of ship oscillation. The diffraction waves are calculated for wave headings ranging from following seas to head seas. The accuracy of a commonly used long wavelength approximation to the Kochin function in which the singularity distribution over the hull surface is collapsed to a line distribution, is also discussed. Keywords: Far field waves; Strip theory; Radiation and diffraction; Kochin function.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1986
- Accession Number
- ADA173448
Entities
People
- Henry T. Wang
Organizations
- United States Naval Research Laboratory