Investigation of Sloshing Effects on Flexible Aircraft Stability and Response.

The present paper provides an investigation of the efects of linear slosh dynamics on aeroelastic stability and response of fying wing confguration. The proposal of this work is to use reduced order model based on the theory of the equivalent mechanical models for the description of the sloshing dynamics. This model is then introduced into an integrated modeling that accounts for both rigid and elastic behavior of fexible aircraft. The formulation also provides for fully unsteady aerodynamics modeled in the frequency domain via doublet lattice method and recast in time-domain state-space form by means of a rational function approximation. The case study consists of the so-called body freedom futter research model equipped with a single tank, partially flled with water, located underneath the center of mass of the aircraft. The results spotlight that neglecting such sloshing efects considering the liquid as a frozen mass may overshadow possible instabilities, especially for mainly rigid-body dynamics.