Problem Solving in Chemical and Biochemical Engineering with POLYMATH,

Chapter 10. Mass Transfer

One-Dimensional Binary Mass Transfer in a Stefan Tube

Concepts Demonstrated

Binary gas phase diffusion of A through stagnant B during evaporation of a pure liquid in a simple diffusion tube.

Numerical Methods Utilized

Numerical integration of simultaneous ordinary differential equations by a shooting technique which must satisfy split boundary conditions.

Problem Statement

Liquid A is evaporating into a gas mixture of A and B from a liquid layer of pure A near the bottom of a cylindrical Stefan tube, as shown in Figure 10-1. The rate of evaporation is relatively slow, so it is a good assumption that the level of the liquid surface is constant. A gas mixture is passing over the upper surface of the Stefan tube. Thus the partial ...