An analytical solution for mass transfer in turbulent falling films with or without chemical reaction

A simple analytical solution is presented for mass transfer in an isothermal turbulent falling liquid film with or without chemical reaction. The exact solutions are compared with previous work for the cases of physical absorption and first-order reaction. New solutions are presented for a zero-order reaction, and generalized results are presented for first and pseudo nth-order reactions. The method of superposition is used to generate the first ten eigenvalues and corresponding values of the Sherwood number for several limiting situations. The analytical solution offers substantial advantages over previous finite-difference numerical solutions both in computation time and in describing the effects of operating variables.