Vibration Characteristics Analysis of Suction Bucket Jacket Offshore Wind Turbine in Different Boundary Conditions

Abstract

[Introduction] The suction bucket jacket is a new type of offshore wind turbine foundation with many advantages, and its vibration characteristics are obviously different from those of traditional foundations. Correctly handling the boundary conditions of the infinite foundation is very important to accurately analyze the vibration problem, so this paper analyzes the vibration characteristics of the suction bucket jacket offshore wind turbine under different boundary conditions. [Method] Taking a suction bucket jacket offshore wind turbine as the analysis object, a full three-dimensional finite element model of structure and soil coupling was established in ANSYS APDL, the influence of boundary conditions on the natural frequency was studied, and the sensitivity analysis of related parameters was carried out. [Result] Different boundary conditions have a great influence on the natural frequency of the whole structure. Changing the boundary conditions has a greater influence on the axial stiffness and torsional stiffness than the bending stiffness of the structure. The natural frequency of the whole structure increases with the spring stiffness of the viscoelastic boundary, the elastic modulus of the soil, and the coefficients of friction between the bucket and soil. [Conclusion] The related factors that affect the calculation accuracy of the natural frequency of the whole structure are analyzed, which can provide references for engineering calculations.

Keywords

• modal analysis
• viscoelastic boundary
• suction bucket jacket
• bucket-soil contact