Popko, W.W.PopkoVorpahl, F.F.VorpahlJonkman, J.J.JonkmanRobertson, A.A.Robertson2022-03-122022-03-122012https://publica.fraunhofer.de/handle/publica/379695This document briefly represents the activities of the Offshore Code Comparison Collaboration (OC3) and Offshore Code Comparison Collaboration Continuation (OC4) projects under the International Energy Agency (IEA) Wind Tasks 23 and 30, focused on advancing the overall accuracy of the coupled simulation tools for offshore wind turbines (OWT). These projects focus on the verification of simulation tools performed by direct code-to-code benchmarking exercises. A methodology of the verification process and its outcome are briefly described. Also an introduction to the state-of-the art simulation of OWT is given.enconference paper