The aerodynamics of the Stardust Sample Return Capsule are analyzed in the lowdensity, transitional ow regime using free-molecular, Direct Simulation Monte Carlo, Navier-Stokes, and Newtonian methods to provide inputs for constructing a transitional ow bridging relation. The accuracy of this bridging relation in reconstructing the aerodynamic coe cients given by the more exact methods is presented for a range of ight conditions and vehicle attitudes. There is good agreement b e t w een the various prediction methods, and a simple sine-squared bridging relation is shown to provide a reasonably good description of the axial force, normal force, and pitching moment o v er a range of Knudsen numbers from 0.001 to 10. The predictions show a static instability of the Stardust capsule in the free-molecular regime that persists well into the transitional ow. The addition of a thin disk to the base of the capsule is shown to remove this static instability. H o w ever, the extremely high entry velocity of 12.6 km s for the proposed trajectory introduces di cult design issues for incorporating this disk caused by the high aerothermal loads that occur even under relatively rare ed conditions.
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