Research on the natural frequencies of an integrated offshore wind turbine model considering blades

The offshore wind turbine (OWT) is a high-rise structure that extremely sensitive to dynamic loads such as wind, waves, and earthquakes. Therefore, in order avoid resonance, it important accurately calculate the natural frequencies of OWT at design stage. integrated finite element model DTU (Technical University Denmark) 10 MW established based on OpenSees software. correctness superstructure simplification method confirmed by comparing calculated analysis software HAWC2 for single-blade fixed constraint bottom tower. mode shapes overall are compared with those mudline concentrated mass top Then, parameters soil shear modulus G0, void ratio e, pile embedded length L, diameter D, water depth, blade stiffness analyzed using lumped tower, some regular conclusions about variation frequency obtained. Finally, model, influence short-term cyclic loading monopiles dense sand studied. results indicate pile-soil interaction has significant impact frequencies, higher second bending OWT, front-after direction more significantly impacted than side-side direction. unlikely affect sand.