Artificial compression methods are used in computational fluid dynamics as a cost‐effective way of solving for the velocity and pressure in a flow. However, relaxation of compressibility in these algorithms yields nonphysical oscillations in the pressure. This report presents analysis and computational tests of time filters to reduce nonphysical acoustic waves in artificial compression methods.
An analysis of the Robert–Asselin time filter for the correction of nonphysical acoustics in an artificial compression method
Artificial compression methods create nonphysical acoustic waves. Time filters, often used in geophysical fluid dynamics, are shown in this paper to selectively damp these acoustics. We analyze the stability of a two‐step artificial compression method with the Robert–Asselin (RA) time filter, and provide tests delineating the filter's positive effects on both stability and accuracy.
more » « less- Award ID(s):
- 1817542
- NSF-PAR ID:
- 10461905
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Numerical Methods for Partial Differential Equations
- Volume:
- 35
- Issue:
- 3
- ISSN:
- 0749-159X
- Page Range / eLocation ID:
- p. 916-935
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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