Abstract

The research activity of this thesis deals with the modelling of mechanical systems and two applications are analyzed by means of the same approach to modelling process. The first application is about the wind energy conversion systems. The modelling activity aimed at representing the behaviour of wind turbines operating in turbulent wind in terms of power conversion performances. The characterization of the test site has been thoroughly presented. Firstly, the concepts and the state of the art of both power curve and turbulence have been examined in detail. Secondly, a model based on a steady instantaneous power curve has been developed starting from the Reynolds approach at turbulence and a procedure to estimate the steady power curve from experimental data has been presented. The model proposed has been used on experimental data collected at the Trento test site to small wind turbines. Finally the model has been validated on experimental data through the comparison on energy capture forecasting. The second application presented deals with the measurement of cylinder roundness by means of multi-point method. The purpose of the modelling activity was the representation of the measurement process of cylinders surface through multi sensor measurement systems. The model has been developed considering step by step the architecture of the measurement system. Firstly, the generic cylinder shape and axis has been modelled in a parametric way. Then the irregular motion during the measurement process has been modelled thanks to a few parameters and finally the sensor disposition and theirs error has been implemented in the model. The parametric model obtained has been used to demonstrate the importance of consider the positioning errors of the sensors and the motion of the cylinder in 3D domain. Finally a three point method for radius and motion reconstruction has been implemented in the model and same Monte Carlo simulation has been carried out to demonstrate the effect of 3D disturbances on shape reconstruction.