# Singularity and Mesh Divergence of Inviscid Adjoint Solutions at Solid Walls

@article{Lozano2022SingularityAM, title={Singularity and Mesh Divergence of Inviscid Adjoint Solutions at Solid Walls}, author={Carlos Lozano and Jorge Pons{\'i}n}, journal={ArXiv}, year={2022}, volume={abs/2201.08129} }

The mesh divergence problem occurring at subsonic and transonic speeds with the adjoint Euler equations is reviewed. By examining a recently derived analytic adjoint solution, it is shown that the explanation is that the adjoint solution is singular at the wall. The wall singularity is caused by the adjoint singularity at the trailing edge, but not in the way it was previously conjectured.

## One Citation

Analytic adjoint solutions for the 2-D incompressible Euler equations using the Green's function approach

- Computer ScienceJournal of Fluid Mechanics
- 2022

The Green's function approach of Giles and Pierce is used to build the lift and drag based analytic adjoint solutions for the two-dimensional incompressible Euler equations around irrotational base flows, and the drag-based adjoint solution turns out to have a very simple closed form in terms of the flow variables.

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