2.019 | Spring 2011 | Undergraduate

Design of Ocean Systems

Labs and Projects

Part II Design: Hydrodynamic Loads and Seakeeping Analysis

Objective

To analyze the seakeeping performance of the FPSO you designed. Both 1-year operation and 100-year survival sea conditions need to be considered. The focus is on the performance of heave, pitch, and roll motion of the ship. The analyses need to be carried out for both light ship (0% loading) and full loaded ship (100% loading).

  1. Determine center of gravity, draft, mass, moment of inertia (roll, pitch and yaw)
  2. Estimate the natural frequencies/periods of heave and pitch
  3. Compute added mass, damping coefficients for a range of frequencies (with periods from 5 seconds to 18 seconds)
  4. Compute wave excitations for a range of frequencies (with periods from 5 seconds to 18 seconds) with incident wave heading angles of 0 (following sea) and 90 (beam sea) degrees
  5. Compute RAOs for a range of frequencies (with periods from 5 seconds to 18 seconds) with incident wave heading angles of 0 (following sea) and 90 (beam sea) degrees
  6. Compare your estimated natural frequencies of heave and pitch with that obtained by numerical computation (i.e. shown in RAOs)
  7. Compute motion spectra of the ship and significant motion amplitude in three incident wave headings
  8. Discuss seakeeping performance of the FPSO you designed and offer suggestions for possible improvements in the design from seakeeping point of view

Software

Any frequency-domain seakeeping analysis tool.

Resources

Guidance for Part 3: Mooring System Design (PDF)