| Popis: |
Previous work by the authors has focused on the optimization of entry aeroshell shapes based solely on objectives related to aeroshell geometry and hypersonic aerodynamic performance. This multi-objective optimization framework has been extended to include the impact of hypersonic aerothermodynamics – that is, aerodynamic heating is now considered alongside the previously-developed objectives. The methodology for performing aerothermodynamic analyses has been adapted from research that has demonstrated the ability to obtain an approximate three-dimensional heating distribution using axisymmetric analyses by matching certain similarity criteria. In the current work, axisymmetric solutions are obtained by coupling Newtonian inviscid solutions with axisymmetric boundary-layer relations that provide an estimate of heat flux. Non-uniform rational B-spline surfaces are used to represent aeroshell shapes. In order to maintain continuity with the previous work, the current aerothermodynamic analysis method is applied to the Mars Science Laboratory mission, in which a heat-rate-minimization objective is traded against objectives to maximize drag-area, static stability, and volumetric efficiency. Two-objective optimizations are performed to highlight major trends and tradeoffs between heat rate and the other three objectives. Results are compared to the baseline 70-degree sphere-cone aeroshell. |
