Norman M. Wereley

Abstract: We will assess the capabilities of physically motivated MR dampers to mitigate ground resonance instability and control the damping level of rotor lag modes. The objectives of this research are threefold: (1) develop a methodology for the integration of the MR damper into a classic linear ground resonance analysis assuming an isotropic rotor hub (all dampers and blades similar) and an anisotropic rotor hub (due to lag damper dissimilarity due to damage, for example), (2) assess whether MR dampers can stabilize a rotor system that exhibits unstable ground resonance, (3) assess whether MR dampers can stabilize a rotor which exhibits unstable ground resonance behavior due to lag damper degradation or damage. The analyses developed in this study show that MR dampers are feasible for achieving these goals.

TL;DR: In this paper, a magnetorheological (MR) based semi-active dampers for the protection of sensitive devices against high shock and impact is examined from design considerations to characterization testing.

TL;DR: In this paper, the authors examined the field-dependent hysteretic behavior of a magnetorheological (MR) fluid and its identification using a Preisach model using first order descending curves.

TL;DR: In this paper, five different models are proposed to predict the field-dependent damping force of an electrorheological (ER) damper and compared with the measured hysteresis loop.