Caratterizzazione del campo di pressione indotto dal vento sul modello di una torre solare

The present work is inspired by some experimental results obtained during experiments in the boundary layer wind tunnels of the university of Bochum (Germany) and CRIACIV (Italy). The experiments were performed on a reduced scale model of a so-called solar chimney (or solar updraft tower), and the wind-induced pressures were measured on several pressure taps on the model surface. The recorded time histories clearly show that the pressure recorded in certain taps oscillates around at least two equilibrium positions, and therefore exhibits marked jumps. Such jumps are distributed irregularly in time and are characterized by a certain degree of randomness. In order for the pressure field to be properly characterized, the pressure is modeled as the output of a non-linear filter with asymmetric potential wells forced by a proper stochastic process. The identification of the system parameters is performed by the comparison between the theoretical distribution of the oscillator response and the histogram of the recorded pressure. The theoretical distribution is in fact available in closed form in the case of a white noise forcing the system. Eventually, the stochastic characteristics of the forcing process are evaluated, verifying whether the hypothesis of a white noise can be accepted.