Mass Transfer Aspects of Pan Evaporation

Abstract

Experimental evaporation data which were obtained with shallow, square pans of different sizes and colors, were studied by means of regression analysis relating evaporation with the difference between the water vapor pressure at the water surface and in the air, pan size, and wind speed at various elevations. These relationships are expressed by different equations for mass transfer whose functional form is widely accepted in the literature, or derivable by means of theoretical diffusion models. A comparison is made of the goodness-of-fit of the different theoretical equations to the experimental data.