Energy transport in the atmospheric boundary layer over the complex ground surface

复杂地表大气边界层的能量传输

• 批准号: 61460046
• 负责人: KONDO Junsei
• 金额: $ 2.69万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-61460046/
• 关键词: Bulk heat transfer coefficient; Canopy flow; Drainage flow; Aerodynamic roughness length; 積雪面粗度; 抵抗係数; 複雑地形; 盆地の気温変化; 複雑地形の熱収支; 複雑地表面の粗度; 斜面流; 盆地冷却; 粗度群落の熱交換

1. Numerical study was made on the bulk heat transfer coefficient for a variety of vegetation types and densities. (1) The bulk transfer coefficients for momentum and heat, Cm and Ch, change with non-dimensional canopy density C*; each has a muximum. (2) The value of Cm is always larger than the value of Ch for a canopy with cm>ch, cm and ch being the drag coefficient and the heat transfer coefficient of an individual canopy element, respectively. (3) The value of C* at which Ch has its maximum value is larger than the value of C* at which Cm has its maximum.2. Three-dimensional distributions of wind speed and temperature in a V-shaped valley covered with a pasture and scattered shrubs were continuously observed. The vertical profile of potential temperature in the drifted cold layer is represented by a linear function of height.The wind speed below the level of maximum wind does not seriously change with a fetch, but the wind speed in the upper part of the cold layer outstandingly increases with a fetch.3. The aerodinamic roughness parameter over inhomogeneous ground surfaces, such as cities, rural towns and so on, is determined by analyzing the wind data at AMeDAS observatories in Japan, by making use of Rossby number similarity theory. Ot is founf that the aerodynamic roughness parameter is proportional to the average size of the roughness elements.

1. 对各种植被类型和密度的体传热系数进行了数值研究。 (1) 动量和热量的整体传递系数 Cm 和 Ch 随无量纲冠层密度 C* 变化；每个都有一个最大值。 (2) 对于冠层来说，Cm 的值总是大于 Ch 的值，其中 cm>ch，cm 和 ch 分别是单个冠层单元的阻力系数和传热系数。 (3)Ch具有最大值时的C*值大于Cm具有最大值时的C*值。2．连续观测了覆盖着牧场和零星灌木的V形山谷中的风速和温度的三维分布。流冷层位温垂直剖面由高度的线性函数表示。最大风级以下的风速随取值变化不大，但冷层上部的风速变化明显。随 fetch.3 的增加而增加。城市、乡镇等不均匀地面的空气动力粗糙度参数是通过分析日本AMeDAS观测站的风数据，利用罗斯贝数相似理论确定的。发现气动粗糙度参数与粗糙度单元的平均尺寸成正比。

项目成果

Kondo,J. and H,Yamazawa: "Aerodynamic roughness over an inhomogeneous ground surface." Boundary-Layer Meteor.35. 331-348 (1986)

近藤，J.

J.Kondo: Boundary-Layer Mateorol.37. 285-296 (1986)

J.Kondo：边界层材料.37。

Kondo,J. and T,Sato: "A simple model of drainage flow on a slope" Bundary-Layer Meteor.42. (1988)

近藤，J.

N.Yasuda: J.Meteorol.Soc.Japan. 64. 283-301 (1986)

N.Yasuda：J.Meteorol.Soc.Japan。

Kondo,J and A,Kawanaka: "Numerical study on the bulktransfer coefficient for a variety of vegetation types and densities." Boundary-Layer Meteor.37. 285-296 (1986)

Kondo,J 和 A,Kawanaka：“各种植被类型和密度的总体传递系数的数值研究。”