Abstract
Aliasing errors arise in the multiplication of partial sums, such as those encountered when numerically solving the Navier-Stokes equations, and can be detrimental to the accuracy of a numerical solution. In this work, a performance and cost analysis is proposed for widely used dealiasing schemes in large-eddy simulation, focusing on a neutrally stratified, pressure-driven atmospheric boundary-layer flow. Specifically, the exact 3/2 rule, the Fourier truncation method, and a high-order Fourier smoothing method are intercompared. Tests are performed within a newly developed mixed pseudo-spectral finite differences large-eddy simulation code, parallelized using a two-dimensional pencil decomposition. A series of simulations are performed at varying resolution, and key flow statistics are intercompared among the considered runs and dealiasing schemes. The three dealiasing methods compare well in terms of first- and second-order statistics for the considered cases, with modest local departures that decrease as the grid stencil is reduced. Computed velocity spectra using the 3/2 rule and the FS method are in good agreement, whereas the FT method yields a spurious energy redistribution across wavenumbers that compromises both the energy-containing and inertial sublayer trends. The main advantage of the FS and FT methods when compared to the 3/2 rule is a notable reduction in computational cost, with larger savings as the resolution is increased (15% for a resolution of 1283, up to a theoretical 30% for a resolution of 20483).
| Original language | English |
|---|---|
| Pages (from-to) | 4069-4084 |
| Number of pages | 16 |
| Journal | Geoscientific Model Development |
| Volume | 11 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 10 Oct 2018 |
Cite this
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Comparison of dealiasing schemes in large-eddy simulation of neutrally stratified atmospheric flows. / Margairaz, Fabien; Giometto, Marco G.; Parlange, Marc B.; Calaf, Marc.
In: Geoscientific Model Development, Vol. 11, No. 10, 10.10.2018, p. 4069-4084.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - Comparison of dealiasing schemes in large-eddy simulation of neutrally stratified atmospheric flows
AU - Margairaz, Fabien
AU - Giometto, Marco G.
AU - Parlange, Marc B.
AU - Calaf, Marc
PY - 2018/10/10
Y1 - 2018/10/10
N2 - Aliasing errors arise in the multiplication of partial sums, such as those encountered when numerically solving the Navier-Stokes equations, and can be detrimental to the accuracy of a numerical solution. In this work, a performance and cost analysis is proposed for widely used dealiasing schemes in large-eddy simulation, focusing on a neutrally stratified, pressure-driven atmospheric boundary-layer flow. Specifically, the exact 3/2 rule, the Fourier truncation method, and a high-order Fourier smoothing method are intercompared. Tests are performed within a newly developed mixed pseudo-spectral finite differences large-eddy simulation code, parallelized using a two-dimensional pencil decomposition. A series of simulations are performed at varying resolution, and key flow statistics are intercompared among the considered runs and dealiasing schemes. The three dealiasing methods compare well in terms of first- and second-order statistics for the considered cases, with modest local departures that decrease as the grid stencil is reduced. Computed velocity spectra using the 3/2 rule and the FS method are in good agreement, whereas the FT method yields a spurious energy redistribution across wavenumbers that compromises both the energy-containing and inertial sublayer trends. The main advantage of the FS and FT methods when compared to the 3/2 rule is a notable reduction in computational cost, with larger savings as the resolution is increased (15% for a resolution of 1283, up to a theoretical 30% for a resolution of 20483).
AB - Aliasing errors arise in the multiplication of partial sums, such as those encountered when numerically solving the Navier-Stokes equations, and can be detrimental to the accuracy of a numerical solution. In this work, a performance and cost analysis is proposed for widely used dealiasing schemes in large-eddy simulation, focusing on a neutrally stratified, pressure-driven atmospheric boundary-layer flow. Specifically, the exact 3/2 rule, the Fourier truncation method, and a high-order Fourier smoothing method are intercompared. Tests are performed within a newly developed mixed pseudo-spectral finite differences large-eddy simulation code, parallelized using a two-dimensional pencil decomposition. A series of simulations are performed at varying resolution, and key flow statistics are intercompared among the considered runs and dealiasing schemes. The three dealiasing methods compare well in terms of first- and second-order statistics for the considered cases, with modest local departures that decrease as the grid stencil is reduced. Computed velocity spectra using the 3/2 rule and the FS method are in good agreement, whereas the FT method yields a spurious energy redistribution across wavenumbers that compromises both the energy-containing and inertial sublayer trends. The main advantage of the FS and FT methods when compared to the 3/2 rule is a notable reduction in computational cost, with larger savings as the resolution is increased (15% for a resolution of 1283, up to a theoretical 30% for a resolution of 20483).
UR - http://www.scopus.com/inward/record.url?scp=85054688241&partnerID=8YFLogxK
U2 - 10.5194/gmd-11-4069-2018
DO - 10.5194/gmd-11-4069-2018
M3 - Article
VL - 11
SP - 4069
EP - 4084
JO - Geoscientific Model Development
JF - Geoscientific Model Development
SN - 1991-959X
IS - 10
ER -