Slamming pressures on a mega yacht

This project was finished in 2003.

General features:

  • Motions in regular head waves
  • 'Worst case' wave: Wave height = 7 m, wave length = 112.8 m
  • Ship speed = 6.2 m/s (12 kn), Fn = 0.250
  • Grid resolution: 220,000 CVs for one vessel side
  • CPU time: 12 hrs for 1 encounter period (5.79 s) on 1 intel P IV 1800 MHz (half model)
  • Results of simulation:
    • Pitch and Heave motions
    • Slamming pressures and integral forces and moments
    • Water on deck
  • Main dimensions of vessel:
    • Loa = 71 m
    • Lwl = 62.5 m
    • T = 3.7 m
    • B = 13.5 m
    • Displ. = 1545.5 t

Coupled simulation of flow and motions (free motions):

Forced-motion simulation:

Drop test with a wedge

This project was completed in 1999.

  • Simulations of 2-D drop tests with a prismatic wedge of 20 deg deadrise and a high aspect ratio (0.61 m x 2.44 m)
  • Validation with experimental data from the Coastal Systems Station (CSS) in the USA
  • Given the initial conditions, the body trajectory, velocity and accelerations (in the planar 3-DOF) are obtained from the flow forces acting on the body, without prescibing the motion
  • From the simulations we obtained the vertical, transverse, and angular accelerations and velocities at each point in the model as a function of time

Asymmetrical drop test

Symmetrical drop test