Toward Automatic Verification of Goal-Oriented Flow Simulations

Nemec, Marian; Aftosmis, Michael J.

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NASA NTRS · 20150000864

Toward Automatic Verification of Goal-Oriented Flow Simulations

Nemec, Marian·Aftosmis, Michael J.

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Abstract

We demonstrate the power of adaptive mesh refinement with adjoint-based error estimates in verification of simulations governed by the steady Euler equations. The flow equations are discretized using a finite volume scheme on a Cartesian mesh with cut cells at the wall boundaries. The discretization error in selected simulation outputs is estimated using the method of adjoint-weighted residuals. Practical aspects of the implementation are emphasized, particularly in the formulation of the refinement criterion and the mesh adaptation strategy. Following a thorough code verification example, we demonstrate simulation verification of two- and three-dimensional problems. These involve an airfoil performance database, a pressure signature of a body in supersonic flow and a launch abort with strong jet interactions. The results show reliable estimates and automatic control of discretization error in all simulations at an affordable computational cost. Moreover, the approach remains effective even when theoretical assumptions, e.g., steady-state and solution smoothness, are relaxed.

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Nemec, Marian, Aftosmis, Michael J.. 2014-08-01. Toward Automatic Verification of Goal-Oriented Flow Simulations. https://ntrs.nasa.gov/citations/20150000864

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