Aa2006-1-33 Static Aeroelastic Analysis of a Thin-film Clamped Ballute for Titan Aerocapture

Many authors have shown the potential mass savings that a ballute can offer for both aerocapture and entry. This mass savings could enhance or even enable many scientific and human exploration missions. Prior to flight of a ballute several technical issues need to be addressed, including aeroelastic behavior. This paper begins to address the issue of aeroelastic behavior by developing and validating the Ballute Aeroelastic Analysis Tool (BAAT). The validation effort uses wind tunnel tests of clamped ballute models constructed of Kapton supported by a rigid nose and floating aft ring. Good correlation is obtained using modified Newtonian aerodynamics and non-linear structural analysis with temperature dependent material properties and thermal expansion. BAAT is then used to compute the deformed shape of a clamped ballute for Titan aerocapture in both the continuum and transitional regimes using impact method aerodynamics and direct simulation Monte Carlo.