Direct numerical simulation of an stably stratified Ekman flow from the Incompact3D Code

Authors

  • Michel Baptistella Stefanello Departamento de Física, Universidade Federal de Santa Maria, RS
  • Leandro Pinto Departamento de Engenharia Sanitária e Ambiental, Universidade Federal de Santa Maria, RS
  • Ricardo Frantz Faculdade de Engenharia, Pontifícia Universidade Católica do Rio Grande do Sul
  • Luca Mortarini The Institute of Atmospheric Sciences and Climate
  • Otávio Costa Acevedo Departamento de Física, Universidade Federal de Santa Maria, RS
  • Jorge Hugo Silvestrini Faculdade de Engenharia, Pontifícia Universidade Católica do Rio Grande do Sul
  • Gervásio Annes Degrazia Departamento de Física, Universidade Federal de Santa Maria, RS

DOI:

https://doi.org/10.5902/2179460X30712

Keywords:

Direct numerical simulation, Ekman layer, Stable layer

Abstract

In a diurnal cycle, distinct thermal and mechanical forcing generates different manifestations of a planetary boundary layer. The stable boundary layer occurs when the soil surface has a lower temperature than the air above. In this layer, wind shear is the main mechanism of turbulence generation. In the present study, a direct numerical simulation of an Ekman layer over a smooth wall is presented to investigate the different turbulent patterns that occur during evolution from a neutral boundary layer to a weakly stable boundary layer. The preliminary study shows the appearance of turbulent structures near the surface, due to the imposition of a stratification.

Downloads

Download data is not yet available.

References

ANSORGE, C.; MELLADO, J. P. Global intermittency and collapsing turbulence in the stratified planetary boundary layer. Boundary-layer meteorology, Springer, v. 153, n. 1, p. 89–116, 2014.

CAUGHEY, S. J. Observed characteristics of the atmospheric boundary layer. In: Atmospheric turbulence and air pollution modelling. [S.l.]: Springer, 1984. p. 107–158.

CAVA, D.; MORTARINI, L.; GIOSTRA, U.; RICHIARDONE, R.; ANFOSSI, D. A wavelet analysis of low-wind-speed submeso motions in a nocturnal boundary layer. Quarterly Journal of the Royal Meteorological Society, Wiley Online Library, v. 143, n. 703, p. 661–669, 2017.

COLEMAN, G. N.; FERZIGER, J.; SPALART, P. A numerical study of the turbulent ekman layer. Journal of Fluid Mechanics, Cambridge University Press, v. 213, p. 313–348, 1990.

FRISCH, U. Turbulence: the legacy of AN Kolmogorov. [S.l.]: Cambridge university press, 1995.

GOHARI, S. I.; SARKAR, S. Direct numerical simulation of turbulence collapse and rebirth in stably stratified ekman flow. Boundary-Layer Meteorology, Springer, v. 162, n. 3, p. 401–426, 2017.

KAIMAL, J.; WYNGAARD, J.; HAUGEN, D.; COTÉ, O.; IZUMI, Y.; CAUGHEY, S.; READINGS, C. Turbulence structure in the convective boundary layer. Journal of the Atmospheric Sciences, v. 33, n. 11, p. 2152–2169, 1976.

LAIZET, S.; LAMBALLAIS, E. High-order compact schemes for incompressible flows: A simple and efficient method with quasi-spectral accuracy. Journal of Computational Physics, Elsevier, v. 228, n. 16, p. 5989–6015, 2009.

LAIZET, S.; LAMBALLAIS, E.; VASSILICOS, J. A numerical strategy to combine high-order schemes, complex geometry and parallel computing for high resolution dns of fractal generated turbulence. Computers & Fluids, Elsevier, v. 39, n. 3, p. 471–484, 2010.

LELE, S. K. Compact finite difference schemes with spectral-like resolution. Journal of computational physics, Elsevier, v. 103, n. 1, p. 16–42, 1992.

MORTARINI, L.; STEFANELLO, M.; DEGRAZIA, G.; ROBERTI, D.; CASTELLI, S. T.; ANFOSSI, D. Characterization of wind meandering in low-wind-speed conditions. Boundary-Layer Meteorology, Springer, v. 161, n. 1, p. 165–182, 2016.

SHAH, S. K.; BOU-ZEID, E. Direct numerical simulations of turbulent ekman layers with increasing static stability: modifications to the bulk structure and second-order statistics. Journal of Fluid Mechanics, Cambridge University Press, v. 760, p. 494–539, 2014.

SPALART, P. R.; COLEMAN, G. N.; JOHNSTONE, R. Direct numerical simulation of the ekman layer: A step in reynolds number, and cautious support for a log law with a shifted origin. Physics of Fluids, AIP, v. 20, n. 10, p. 101507, 2008.

SUN, J.; MAHRT, L.; BANTA, R. M.; PICHUGINA, Y. L. Turbulence regimes and turbulence intermittency in the stable boundary layer during cases-99. Journal of the Atmospheric Sciences, v. 69, n. 1, p. 338–351, 2012.

Published

2018-03-22

How to Cite

Stefanello, M. B., Pinto, L., Frantz, R., Mortarini, L., Acevedo, O. C., Silvestrini, J. H., & Degrazia, G. A. (2018). Direct numerical simulation of an stably stratified Ekman flow from the Incompact3D Code. Ciência E Natura, 40, 107–111. https://doi.org/10.5902/2179460X30712

Most read articles by the same author(s)

<< < 1 2 3 4 5 6 7 8 9 10 > >>