Advertisement

Moscow University Physics Bulletin

, Volume 73, Issue 6, pp 710–715 | Cite as

Laboratory and Numerical Modeling of a Stably Stratified Wind Flow over a Water Surface

  • D. A. SergeevEmail author
  • O. A. DruzhininEmail author
  • Yu. I. TroitskayaEmail author
  • W. T. Tsai
  • M. I. Vdovin
  • A. A. Kandaurov
PHYSICS OF EARTH, ATMOSPHERE, AND HYDROSPHERE
  • 5 Downloads

Abstract

The objective of this paper was to perform laboratory modeling and direct numerical simulation of a turbulent wind flow over a water surface under stable stratification conditions of the air boundary layer. Laboratory and numerical experiments were carried out with the same bulk Reynolds (Re) and Richardson (Ri) numbers, which first allowed direct comparison between measurements and calculations. A wind flow with an air–water temperature difference of up to 20°C and a relatively low wind speed (up to 3 m/s) were obtained in laboratory experiments in the wind–wave flume of the large thermostratified tank at the Institute of Applied Physics of the Russian Academy of Sciences. This allowed a sufficiently strong stable stratification with a bulk Richardson number of up to 0.04. The air velocity is obtained using both contact (a Pitot tube) and particle image velocimetry methods. At the same time, the air temperature profile is also measured by a set of contact probes. Analogous bulk Richardson and Reynolds numbers are prescribed in the direct numerical simulation, where the turbulent Couette flow is considered as a model of the near water constant-stress atmospheric boundary layer. The mean velocity and temperature profiles obtained in our laboratory and numerical experiments agree well; they are also predicted well by the Monin–Obukhov similarity theory. The experimental results state that sufficiently strong stratification, although it allows a statistically stationary turbulent regime, leads to a sharp decrease in momentum and heat fluxes. For this regime it is demonstrated that the turbulent Reynolds number for the boundary layer (based on the Obukhov length-scale and friction velocity) satisfies the known criterion that characterize stationary strongly stratified turbulence.

Keywords:

boundary layer wind waves stratification numerical simulation laboratory experiment 

Notes

ACKNOWLEDGMENTS

This study was carried out under the financial support of the Russian Foundation for Basic Research (grants nos. 17-05-00703, 18-05-00265, and 16-55-52022), of the President of the Russian Federation (nos. SP-1740.2016.1 and MK-2041.2017.5). The numerical computations and development of the temperature control system in the wind–wave flume were supported by the Russian Science Foundation (grants nos. 14-17-00667 and 15-17-20009, respectively).

The experiments were carried out in the unique scientific complex of large-scale geophysical facilities (http://ckp-rf.ru/usu/77738).

REFERENCES

  1. 1.
    A. S. Monin and A. M. Yaglom, Statistical Fluid Mechanics: Mechanics of Turbulence (MIT Press, 1971), Vol. 1.Google Scholar
  2. 2.
    D. Melas, Boundary-Layer Meteorol. 48, 361 (1989).ADSCrossRefGoogle Scholar
  3. 3.
    P. J. Mulhearn, Boundary-Layer Meteorol. 21, 247 (1981).ADSCrossRefGoogle Scholar
  4. 4.
    L. Mahrt, Annu. Rev. Fluid Mech. 46, 23 (2014). doi 10.1146/annurev-fluid-010313-141354ADSMathSciNetCrossRefGoogle Scholar
  5. 5.
    Y. Ohya, D. Heff, and R. N. Meroney, Boundary-Layer Meteorol. 83, 139 (1997).ADSCrossRefGoogle Scholar
  6. 6.
    O. Flores and J. J. Riley, Boundary-Layer Meteorol. 139, 241 (2001).ADSCrossRefGoogle Scholar
  7. 7.
    O. A. Druzhinin, Yu. I. Troitskaya, and S. S. Zilitinkevich, Q. J. R. Meteorol. Soc. 142, 759 (2016). doi 10.1002/qj.2677ADSCrossRefGoogle Scholar
  8. 8.
    Y. I. Troitskaya, D. A. Sergeev, A. A. Kandaurov, G. A. Baidakov, M. A. Vdovin, and V. I. Kazakov, J.  Geophys. Res. 117, C00J21 (2012). doi 10.1029/2011JC007778Google Scholar
  9. 9.
    D. A. Sergeev, Instrum. Exp. Tech. 52, 438 (2009). doi 10.1134/S0020441209030257CrossRefGoogle Scholar

Copyright information

© Allerton Press, Inc. 2018

Authors and Affiliations

  1. 1.Institute of Applied Physics, Russian Academy of SciencesNizhniy NovgorodRussia
  2. 2.Lobachevsky State University of Nizhny NovgorodNizhny NovgorodRussia
  3. 3.National Taiwan UniversityTaipeiTaiwan

Personalised recommendations