AN APPROXIMATE SOLUTION OF A QUASI- LINEAR DIFFUSION PROBLEM TABLES AND NOMOGRAMS FOR CONCENTRATION IN SLABS IN A SPECIAL CASE

摘要

For a number of years, one of the present authors, S.E. Pihlajavaara, has been engaged in research work on the drying of concrete[l]. The diffusion theory constitutes the basis of the mathematical treatment of the problem involved. The diffusion-type of equation, with diffusivity dependent upon concentration, has aroused particular interest, and some years ago nomograms were published on the drying of a concrete slab with the moisture conductivity "(diffusivity) linearly dependent upon moisture [2]. The task of finding solutions for the cases in which the diffusivity is more generally dependent upon concentration was entrusted to Mr S. Kasi, M.Sc. (Eng.), Assistant of Physics at the Technical University of Helsinki.