|
|||||
|
|
Mitigating horizontal divergence “checker-board” oscillations on unstructured triangular C-grids for nonlinear hydrostatic and nonhydrostatic flows |
|
| Institution: | 2. Institute for Advanced Computational Science, Stony Brook University, Stony Brook, New York, USA;3. Computational Science Center, Brookhaven National Laboratory, Upton, New York, USA;1. Adjunct Professor, Computational Science Research Center, San Diego State University, CA, USA;2. Research Assistant Professor, Departamento de Matemáticas y Estadística, Universidad del Norte, Barranquilla, Colombia |
| Abstract: | A complication of finite-volume triangular C-grid methods is the numerical emergence of horizontal divergence errors that lead to grid-scale oscillations in vertical velocity. Nonlinear feedback via advection of momentum can lead to numerical instability in velocity modes via positive feedback with spurious vertical velocities induced by horizontal divergence truncation error. Existing strategies to mitigate divergence errors such as direct divergence averaging and increased diffusion do not completely mitigate horizontal vertical velocity oscillations. We present a novel elliptic filtering approach to mitigate this spurious error and more accurately represent vertical velocities via improved calculation of horizontal divergences. These results are applied to laminar curved channel flows, demonstrating the applicability of the method to reproduce secondary flow features. |
| Keywords: | Unstructured mesh modeling Triangular C-grid Implicit (elliptic) and explicit filtering Horizontal divergence error Secondary circulation |
| 本文献已被 ScienceDirect 等数据库收录！ | |