Abstract
Offshore wind turbines (OWTs) are considered as an important element of the future energy infrastructure. The majority of operational OWTs are founded on monopiles in water depths up to 30 m. Alternative foundation arrangements, however, are needed for future development rounds in deeper waters. To date, there have been no long-term observations of the performance of these relatively novel structures, although the monitoring of a limited number of OWTs has indicated a departure of the system dynamics from the design requirements. Lack of data concerning long-term performance indicates a need for detailed investigation to predict the future performance of such structures. Arguably this can be best carried out through small-scale laboratory experimental investigation, whose results are interpreted based on appropriate scaling laws. In this chapter, scaling laws are derived for the design of such model tests, which can be used for studying the long-term performance of small-scale wind turbines and prediction of the prototype response.