Unsteady Output-Based Adaptation Using Continuous-in-Time Adjoints
نویسنده
چکیده
We present a method for estimating spatial and temporal numerical errors in scalar outputs of unsteady fluid dynamics simulations using a continuous-in-time adjoint solution and general time-integration methods. A continuous formulation decouples the primal and adjoint temporal discretizations and allows the use of standard time-integration schemes for the adjoint. For non-variational methods, a scheme-agnostic temporal reconstruction of the primal and adjoint solutions replaces the functional representation in between time nodes. Finally, projection of the adjoint to a semi-refined space yields separate measures of the errors in space and time, which then drive adaptive refinement of the spatial and temporal discretizations. Results for the Euler equations and the compressible Navier-Stokes equations demonstrate accuracy of the error estimates and effectiveness of the adaptation.
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تاریخ انتشار 2017