Client

Oil Company

Objective

Static and dynamic FEM (ANSYS) analysis of a general riser system in order to evaluate the loads, deflections and tensions caused by the environmental conditions due to waves, current, pretension and weight. Pipes with different characteristics have been analysed

Scope

  • Static analyzes:
    The rotational stiffness for the flex joints has been considered in the study. The following analyses has been performed for excursions of 50, 40, 30, 20, 10 and 0 m, deformed statically
  •       o Wave height of 10 m, period of 10 s and surface current speed corresponding to the exceedance of 1%
          o Wave height of 5 m, period of 7 s and surface current speed corresponding to the exceedance of 5%
          o Maximum current speed

  • Modal analysis
  • Analysis of VIV
  • Fatigue analysis
  • Dynamic analyzes:
  •       o Wave frequency motion (RAOs) for small, medium and large waves
          o Slow drift motions with periods of 100 and 200 seconds