A COMPARISON STUDY OF UNCERTAINTY ANALYSIS APPROACHES FOR ROTOR DYNAMICS APPLICATIONS

Arinan Dourado Guerra Silva¹; Aldemir Ap Cavalini Jr¹; Valder Steffen Jr¹

¹ Federal University of Uberlândia

doi:10.20906/CPS/COB-2015-0409

Resumo

The models of mechanical systems are inherently uncertain due to design fluctuations or to lack of knowledge. Thus, it is essential to have a methodology that takes into account these uncertainties as efficiently as possible. Considering the various existing methods for modeling uncertainties in mechanical models, the stochastic approach and the fuzzy logic are found among the most widely used. Each approach has its pros and cons and the knowledge of these features aids the choice of which methodology would be more appropriate in a given application. Therefore, this paper aims at analyzing the characteristics and performance of these two approaches. For this purpose, a flexible rotor with operational uncertainties was modeled by using both stochastic methodologies and fuzzy logic as based on the so-called α - optimization method. Through numerical simulations the methodologies have been compared in terms of orbits and frequency response functions.

Palavras-chave: stochastic analysis; fuzzy analysis; rotor dynamics