Numerical Analysis of Hydrodynamic Characteristics for Various Types of Jack-up Legs

다양한 형상의 Jack-up Leg에 대한 해양 동역학적 수치해석

  • Received : 2013.10.21
  • Accepted : 2014.08.14
  • Published : 2014.10.31


In this study, the hydrodynamic characteristics of various types of jack-up legs for a wind turbine installation vessel were analyzed. Using the modified Morison equation, the wave and current excitation forces on the jack-up legs were calculated. A modal analysis was performed to predict the dynamic responses for various types of jack-up legs. The Newmark-beta time integration scheme was used to solve the equation of motion in waves in the time domain. The maximum displacement and maximum bending stress were computed for four different types of legs, and their results were compared to select an optimum leg type. Finally, a six-leg jack-up rig with the selected optimal legs was modeled, and its natural period and hydrodynamic behaviors were evaluated.


Offshore wind turbine installation vessel;Jack-up leg;Morison equation;Modal analysis;Newmark-beta method;Natural period


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Cited by

  1. Dynamic Response and Reliability of Six-Leg Jack-Up Type Wind Turbine Installation Vessel vol.17, pp.03, 2017,


Supported by : 인하대학교