Seminario del prof. Marco Belloli, del Politecnico di Milano, su
Scalatura delle macchine eoliche per prove in galleria del vento e in vasca navale
il 28 marzo 2018, alle ore 11, presso l’Aula Magna della Facoltà di Ingegneria.
L’attività è organizzata in collaborazione con l’associazione E.U.Re.Ca.
Floating offshore wind turbine can overcome the actual limits of offshore wind installations, all of which consists of conventional fixed- bottom foundation technology located in relatively shallow water depths (<40m) and near to shore (<30km). In response to this challenge, momentum is building around the potential for floating offshore wind foundation technology to unlock near-shore deep water sites at a lower cost of energy than far-shore fixed-bottom locations, in other words floating wind turbines are well suited for far shore locations where regular high wind speeds, can improve the performances in power generation reducing the LCOE. On the other hand floating wind poses very important engineering challenges, because of the intrinsic nature of the FOWTs. These machines are subjected to wave and wind actions in a very challenging environment and they are in their early stages so there is a clear need to have validated numerical models for design and optimization. Experimental testing is crucial for providing the data base for the model benchmarking and lab testing can be a very useful approach because of the controlled input.
Because of the complexity of the physics of a floating offshore wind turbine, due to the interaction of aerodynamic and hydrodynamic problems it is important to perform experimental tests for code validation purposes. Nevertheless, because of the conflicting scaling laws governing the two physical domains (i.e. Froude/Reynolds conflict) it is hard to design scale models and experiments properly describing the full scale operating conditions, reproducing contemporary wind and waves in laboratory. For this reason, recent project is being investigating the implementation of Hardware-In-The-Loop (HIL) hybrid testing for studying floating offshore wind turbines, where the model is subjected both to experimentally measured and numerically computed forces, in real time. In the wave basin, the real-time forcing system is a set of fish lines with spring in series actuated by electrical motors (force control), reproducing aerodynamic forces while in the wind tunnel, a 2 degree- of-freedom (DoF) or 6 DoF robot, provides the motion to the wind turbine model (motion control).
The seminar will report non-trivial methodological and technical aspects of the wind tunnel setup to test floating offshore wind turbines, focusing on contrasting scaling issues, with particular reference on the aeroelastic and hydroelastic scaling but also considering the implementation of the wind turbine control system.
NOEL: Lecture of Professor Marco Belloli from Politecnico Milano