Gust Loads Alleviation Using Sloshing Fuel

There is much interest in developing concepts to reduce in-flight loads resulting from gusts and atmospheric turbulence, as this will lead to lighter aircraft with improved fuel performance and reduced environmental impact. Recent work has considered using sloshing in tanks as a means to increase the effective structural damping in the wings. Experimental studies have quantified the effect that sloshing can have on simple systems, and these studies have been complemented by the development of equivalent mechanical models to efficiently model the process and provide a design capability. This paper provides an initial study to evaluate the benefits of fuel tank sloshing on the response of a simple simulated aeroelastic wing model subjected to "one minus cosine" vertical gust sequences. The effects of the filling level and tank position upon loads alleviation are explored. It is shown that the sloshing fuel can increase the damping level in the gust response, but is dependent upon the tank filling level, and tank size and position.