Some Experiments on Evaporation from Finite Surfaces

[摘要] Experiments on evaporation were carried out in wind tunnels. The results were in fairly good agreement with the theoretical results by Yamamoto and Ogiwara.When the boundary layer on the surface of water is laminar, the mean rate of evaporation, E, is expressed by the formula, where E is measured in g. cm. sec., u1; the wind velocity outside of the boundary layer, in cm-2 sec-1., x; the length of the veesel along wind, in cm., c0, c1; vapour concentrations on water surface and in an air current outside the boundary layer respectively, in g. cm-3. When the boundary layer on the surface of water is turbulent:In our experiment where water was constrained by the blotting paper the surface remained in laminar condition until log_??_, and beyond then it changed into turbulent condition and no transition region could be seen. But, as is seen from Millar's experiment, if we use the ves. sel containing water only, the surface of water will turn to turbulent condition even when log_??_, and the rate of evaporation from free water surface will be

[学科分类] 大气科学