roughness length

基本解釋

For the usual velocity profile method, four kinds of method are given: 1) Estimating roughness length from velocity time series of two near-bottom layers;
針對使用較常見的流速剖面法，本文介紹了四種方法1）近底兩層流速時間系列估計粗糙長度；
Some relationships of roughness length, friction velocity and resistance coefficient with wind velocity and wave height in neutral stratification have been given.
給出了中性層結(jié)時水面粗糙度、動力摩擦速度及阻力系數(shù)與風速和浪高的關(guān)系。
A linear correlation exists between the current speed of adjacent layers, and the correlation is dependent on the height of the layer above the seabed, roughness length and shear velocity.
相鄰層位的流速在時間序列上存在很高的線性關(guān)系，回歸直線的斜率與水層距底床的高度、粗糙長度和摩阻流速有關(guān)。

粗糙度
Wind velocity and roughness length influence the friction velocity, the range of average friction velocity is 0.0580.092m/s. The threshold friction velocity of the soil surface is about 0.082m/s, less than the surface covered by vegetation, sand, large particle.
摩阻風速受風速和地表粗糙度的影響,日平均摩阻風速最大變化范圍是0.058～0.092m/s。
生物學
粗糙長度
Calculated friction velocity caused by tidal current (u*_c)) is 0.39～6.8cm/s. Roughness length z_0=0.31cm.
計算得出潮流摩阻流速u*_c。范圍為0.39～6.8cm/s,粗糙長度Z0=0.31cm。
水利工程
粗糙長度