We present a compatible finite element discretisation for the vertical slice compressible Euler equations, at next-to-lowest order (i.e., the pressure space is bilinear discontinuous functions). The equations are numerically integrated in time using a fully implicit timestepping scheme which is solved using monolithic GMRES preconditioned by a linesmoother. The linesmoother only involves local operations and is thus suitable for domain decomposition in parallel. It allows for arbitrarily large timesteps but with iteration counts scaling linearly with Courant number in the limit of large Courant number. This solver approach is implemented using Firedrake, and the additive Schwarz preconditioner framework of PETSc. We demonstrate the robustness of the scheme using a standard set of testcases that may be compared with other approaches.
@article{arxiv.2210.07861,
title = {A compatible finite element discretisation for the nonhydrostatic vertical slice equations},
author = {C. J. Cotter and J. Shipton},
journal= {arXiv preprint arXiv:2210.07861},
year = {2023}
}
Comments
Response to reviewers. Thanks to Golo Wimmer for pointing out the wrong factor of h in the interior penalty for diffusion - this was also wrong in the codes and we reran the dense bubble testcases