Momentum and mass transfers in the surface boundary layer
Momentum and mass transfers in the surface boundary layer
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表面边界层中的动量和质量传递
DOI：
10.1002/qj.49709942014
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发表时间：
1973
影响因子：
8.9
通讯作者：
F. Lourence
中科院分区：
文献类型：
--
作者：
W. Pruitt;D. Morgan;F. Lourence
结果来自 1966 年和 1967 年在加利福尼亚州戴维斯的草坪上进行的六项微气象研究。来自 6·1 m 直径的非常灵敏的蒸渗仪的高度可靠的表面阻力和蒸发数据为评估对空气动力学预测方程重要的几个参数提供了绝佳的机会。
对于六项研究，平均冯卡门常数 k 的范围为 0·40 至 0·44，强烈支持继续接受 k 在 0·42 左右。
人们发现 Monin-Obukhov (1954) 的通用 ψM 函数在近自由对流下变化为 ∣Ri∣−1/3，这表明非绝热剖面效应比 Sellers (1965) 给出的 KEYPS 剖面形式所建议的要大得多。
经验关系为 −3·5 < Ri < 0·3 范围内的实验数据提供了极好的拟合，对于不稳定和稳定条件，分别为 phiM = (1–16 Ri)−1/3 和 phiM = (1 + 16Ri)1/3。对于 Φw，相应的表达式为 Φw = ·885 (1–22 Ri)−.40 和 Φw = ·885 (1+34 Ri).40。
KW/KM 比率显示出从中性时的 1·13 到强稳定条件下的 0·75 左右的值的系统性下降，这与最近关于 KH/KM 在大范围稳定条件下没有变化的报道相矛盾（Laykhtman 和 Panomareva 1969；Webb 1970；Oke 1970）。 UCD 结果与文献基本一致，KW/KM 随着不稳定性的增加而系统性地增加。在0>Ri>-2·0范围内，KW/KM从1·13增加到1·6。
由于 Davis z/L 数据的不确定性，没有给出将 ΦM 和 ΦW 或 KW/KM 与 z/L 相关的表达式。然而，在几项已发表的 z/L (Ri) 关系中使用 Davis Ri 数据，可以与之前的研究结果进行有限的比较。
Results are presented from six micrometeorological studies conducted over a grass turf at Davis, California, in 1966 and 1967. Highly reliable surface drag and evaporation data from very sensitive lysimeters of 6·1 m diameter afforded excellent opportunity to evaluate several parameters important to aerodynamic-prediction equations.
For the six studies the mean von Karman constant, k, ranged from 0·40 to 0·44, strongly supporting continued acceptance of k at around 0·42.
The Monin-Obukhov (1954) universal ϕM function was found to vary as ∣Ri∣−1/3 under near-free convection, indicating significantly greater diabatic profile effects than suggested in the form of the KEYPS profile as given by Sellers (1965).
Empirical relationships providing excellent fit to experimental data for the range −3·5 < Ri < 0·3, were ϕM = (1–16 Ri)−1/3 and ϕM = (1 + 16Ri)1/3 respectively for unstable and stable conditions. For ϕw corresponding expressions were ϕw = ·885 (1–22 Ri)−.40 and ϕw = ·885 (1+34 Ri).40.
The ratio KW/KM showed a systematic drop from 1·13 at neutral to a value around 0·75 under strongly stable conditions, which conflicts with recent reports of no change of KH/KM within a wide range of stable conditions (Laykhtman and Panomareva 1969; Webb 1970; Oke 1970). The UCD results are in general agreement with the literature in that KW/KM systematically increased with increasing instability. In the range 0 > Ri > −2·0, KW/KM increased from 1·13 to 1·6.
No expressions relating ϕM and ϕW or KW/KM to z/L are presented due to uncertainties in Davis z/L data. However, use of Davis Ri data in several published z/L (Ri) relationships, allowed a limited comparison with results of previous studies.