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Adjoint-Based Adaptive Meshing in a Parallel Setting



This work analyzes the drag performance of six axis-symmetric shroud shapes over the ascent trajectory of the Saturn V launch vehicle. An adjoint-based adaptive meshing algorithm is used to generate accurate predictions of the vehicle’s performance. Moreover, solving the adjoint equations enables the estimation of local gridinduced errors on the functional of interest (such as lift or drag). These local errors are used to focus mesh refinement on the most influential regions, thereby improving the functional’s accuracy and maintaining a low computational cost. Combined with a highly efficient parallel flow solver, this approach is shown to be an effective aid to the aerodynamic design of new launch vehicles. A metric known as ‘drag loss’ is integrated over the flight trajectory and is used to compare the shrouds’ overall drag performance. The results reported in this paper were computed using the NASA software package Cart3D on the Columbia supercomputer located at NASA Ames Research Center, and the procedures and tools are currently employed in the initial design studies of the Ares V Heavy Lift Launch Vehicle (HLLV).

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