Study of airfoil gust response alleviation using an electro-magnetic dry friction damper. Part 1: Theory

An electro-magnetic controllable dry friction damper has been designed and numerically simulated. The gust response of a three degree-of-freedom typical airfoil section with a control surface using this non-linear damper has been studied theoretically. The effects of the different gust excitations and parameter variations of the non-linear damper on the non-linear aeroelastic response are discussed. The numerical results show the present electro-magnetic dry friction damper can be used to alleviate the dynamic response to both a periodic and a linear frequency sweep gust excitation, especially for the plunge and pitch responses. The results are also verified by an experimental investigation in a wind tunnel presented in a companion paper, Part 2.