Course

Seakeeping and Manoeuvring

Indian Institute of Technology Kharagpur

Course outline:

Seakeeping: Regular water waves – definition of ship motions – single degree of freedom motions in regular waves – uncoupled heave, pitch and roll motions – coupled heave and pitch motions – irregular waves - description of long crested waves by 2D spectrum – ship motions in 2D irregular waves – description of short-crested sea – ship motions in 3D irregular waves – dynamic effects – deck-wetness, slamming, relative motions, sea-sickness etc. – added resistance in waves – roll stabilization.

Manoeuvring: Types of directional stability - linear equations of motions in horizontal plane – hydrodynamic derivatives – stability index – standard manoeuvres – turning circle, zigzag, pullout and spiral manoeuvres – roll during turn – experimental determination of hydrodynamic derivatives – straight-line, rotating arm and PMM experiments – description of control surface (rudder) – control derivatives.

Course topics:

  1. Regular water waves
  2. Definition of ship motions
  3. Single degree of freedom motions in regular waves
  4. Uncoupled heave, pitch and roll motions
  5. Coupled heave and pitch motions
  6. Irregular waves
  7. Description of long crested waves by 2D spectrum
  8. Ship motions in 2D irregular waves
  9. Description of short-crested sea
  10. Ship motions in 3D irregular waves
  11. Dynamic effects - deck-wetness, slamming, etc.
  12. Added resistance in waves
  13. Roll stabilization
  14. Types of directional stability
  15. linear equations of motions in horizontal plane
  16. hydrodynamic derivatives
  17. stability index
  18. standard manoeuvres
    • zigzag, pullout and spiral manoeuvres
    • turning circle
    • roll during turn
  19. concept of nonlinear derivatives
  20. experimental determination of hydrodynamic derivatives
    • straight-line tests
    • rotating arm tests
    • PMM experiments
  21. description of control surfaces (rudder)
  22. control derivatives
Course Lectures