Simulation and scaling analysis of periodic surfaces with small-scale roughness in turbulent Ekman flow

被引:1
|
作者
Kostelecky, Jonathan [1 ,2 ]
Ansorge, Cedrick [1 ]
机构
[1] Free Univ Berlin, Inst Meteorol, Carl Heinrich Becker Weg 6 10, D-12165 Berlin, Germany
[2] Univ Cologne, Inst Geophys & Meteorol, Pohlig Str 3, D-50969 Cologne, Germany
关键词
topographic effects; turbulent boundary layers; meteorology; DIRECT NUMERICAL-SIMULATION; LARGE-EDDY SIMULATION; IMMERSED BOUNDARY METHOD; VON KARMAN CONSTANT; CHANNEL FLOW; GLOBAL INTERMITTENCY; COMPACT SCHEMES; REYNOLDS-NUMBER; APPARENT RANGE; HEAT-TRANSFER;
D O I
10.1017/jfm.2024.542
中图分类号
O3 [力学];
学科分类号
08 ; 0801 ;
摘要
Roughness of the surface underlying the atmospheric boundary layer causes departures of the near-surface scalar and momentum transport in comparison with aerodynamically smooth surfaces. Here, we investigate the effect of 56 x 56 homogeneously distributed roughness elements on bulk properties of a turbulent Ekman flow. Direct numerical simulation in combination with an immersed boundary method is performed for fully resolved, three-dimensional roughness elements. The packing density is approximately 10% and the roughness elements have a mean height in wall units of 10 less than or similar to H+ less than or similar to 40. According to their roughness Reynolds numbers, the cases are transitionally rough, although the roughest case is on the verge of being fully rough. We derive the friction of velocity and of the passive scalar through vertical integration of the respective balances. Thereby, we quantify the enhancement of turbulent activity with increasing roughness height and find a scaling for the friction Reynolds number that is verified up to R-tau approximate to 2700. The higher level of turbulent activity results in a deeper logarithmic layer for the rough cases and an increase of the near-surface wind veer in spite of higher Re-tau. We estimate the von Karman constant for the horizontal velocity kappa(m) = 0.42 (offset A = 5.44) and for the passive scalar kappa(h) = 0.35 (offset A = 4.2). We find an accurate collapse of the data under the rough-wall scaling in the logarithmic layer, which also yields a scaling for the roughness parameters z-nought for momentum (z(0m)) and the passive scalar (z(0h)).
引用
收藏
页数:33
相关论文
共 50 条
  • [1] Surface Roughness in Stratified Turbulent Ekman Flow
    Kostelecky, Jonathan
    Ansorge, Cedrick
    BOUNDARY-LAYER METEOROLOGY, 2025, 191 (01)
  • [2] Stationary scaling in small-scale turbulent dynamo problem
    Kopyev, A., V
    Il'yn, A. S.
    Sirota, V. A.
    Zybin, K. P.
    PHYSICAL REVIEW E, 2020, 101 (06)
  • [3] Numerical simulation of the structure of fully developed turbulent flow in a small-scale zone
    Chernykh, G. G.
    Baev, M. K.
    RUSSIAN JOURNAL OF NUMERICAL ANALYSIS AND MATHEMATICAL MODELLING, 2010, 25 (04) : 289 - 302
  • [4] Simulation of turbulent square-duct flow: Dissipation and small-scale motion
    Huser, A
    Biringen, S
    AIAA JOURNAL, 1996, 34 (12) : 2509 - 2513
  • [5] Simulation of turbulent magnetic reconnection in the small-scale solar wind
    Fengsi Wei
    Qiang Hu
    Xueshang Feng
    Schwen R.
    Science in China Series A: Mathematics, 2000, 43 : 629 - 637
  • [6] Simulation of turbulent magnetic reconnection in the small-scale solar wind
    Wei, FS
    Hu, Q
    Schwen, R
    Feng, XS
    SCIENCE IN CHINA SERIES A-MATHEMATICS PHYSICS ASTRONOMY, 2000, 43 (06): : 629 - 637
  • [7] Direct numerical simulation of turbulent liquid-solid flow in a small-scale stirred tank
    Chang, Qi
    Di, Shengbin
    Xu, Ji
    Ge, Wei
    CHEMICAL ENGINEERING JOURNAL, 2021, 420 (420)
  • [8] Small-scale turbulent dynamo
    Chertkov, M
    Falkovich, G
    Kolokolov, I
    Vergassola, M
    PHYSICAL REVIEW LETTERS, 1999, 83 (20) : 4065 - 4068
  • [10] ON ALIGNMENTS AND SMALL-SCALE STRUCTURE IN TURBULENT PIPE-FLOW
    TSINOBER, A
    EGGELS, JGM
    NIEUWSTADT, FTM
    FLUID DYNAMICS RESEARCH, 1995, 16 (05) : 297 - 310