Vertical Plane Motions of SWATH (Small Waterplane Area Twin Hull) Ships in Regular Waves

摘要

The vertical plane motions of SWATH ships are theoretically modeled. Strip theory is used to evaluate hydrodynamic forces. Contributions due to body lift, cross flow drag, and fin lift dominate the damping coefficients. Consequently, their accurate modeling is vital to the accuracy of motion predictions. Semiempirical methods developed for evaluating these components are described. Data for oscillating two-dimensional cylinders, flat plates, and pairs of fins as well as semiempirical expressions for submarine hydrodynamic coefficients have been utilized in this development. Correlation between predicted and experimental results are presented for hydrodynamic coefficients, exciting force and moment, and responses to regular waves. The expressions developed result in correlation which is good and which is notably better than results reported previously.