Theoretical Prediction of Motion of Small-Waterplane-Area, Twin-Hull (SWATH) Ships in Waves.
Abstract
Linear equations of motion with the hydrodynamic coefficients approximated by strip method are used to obtain the motion of small-waterplane-area, twin-hull (SWATH) ships in regular and irregular waves. The couplings among different modes of motion are separated into 3 independent groups: surge, heave-pitch and sway-roll-yaw; and the resulting equations of motions are treated in the frequency domain. The hydrodynamic coefficients of predominantly nonviscous nature, added mass and wavemaking damping, are obtained by strip theory. The effects of wave diffraction, viscous damping, and stationary stabilizing fins are included in the equations of motion within the framework of the linear frequency response of a body to waves. The assumptions involved in the evaluation of various hydrodynamic coefficients in the equation of motion are specified. The validity of the theoretical prediction of motion is checked by correlating with existing model experimental results, and the relevant discussions are made. In general, the theoretical prediction is satisfactory except the case of near zero-encounter frequency which can occur when a ship cruises with certain speed in stern-quartering waves.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1976
- Accession Number
- ADA033912
Entities
People
- C. M. Lee