On the Evaporation of Water from a Vessel of Finite Dimensions in the Case of Laminar Boundary Layer-Supplementary Report

Abstract

Formerly the author investigated this problem using the Blasius' result on the velocity distribution in the boundary layer. The velocity distribution in the boundary layer has been calculated by Pohlhausen from the momentum equation of boundary layer and in the present paper the same method was applied to the diffusion equation of water vapour to obtain a formula expressing the rate of evaporation of water. The result was given as where M is the rate of evaporation of water from a vessel of which breadth and length are i and L respectively; C₀, C∞ concentration of water vapour on the surface of water and outside the boundary layer; h the diffusion codf. of water vapour through the air; U_??_ the velocity of the air; V the kinematic viscosity of the air. Comparing this with the result formerly obtained in which the coef. of evaporation was 0.555 both results may be considered to be fairily in agreement.