# Transport Phenomena II

## Objectives

Understanding of mass transfer fundamentals. Mathematical formulation of mass transfer problems for different geometries.Evaluation of diffusion coefficients and mass transfer coefficients.

## General characterization

10678

6.0

##### Responsible teacher

Isabel Maria Rola Coelhoso

Weekly - 4

Total - 70

Português

n/a

### Bibliography

Cussler, E.L., " Diffusion: mass transfer in fluid systems", 3rd ed., Cambridge University Press, UK, 2009.

Bird, R.B.; Stewart, W.E.; Lightfoot, E. N. Transport Phenomena. 2nd ed. J Wiley & Sons, 2007.

Welty, J.R; Wicks, C.E.; Wilson, R.E.; Rorrer G.L. Fundamentals of momentum, heat and mass transfer. 5th ed. John Wiley &Sons, Inc, N.Y., 2010.

### Teaching method

The teaching comprises lectures and solving problems sessions which cover all the contents according to the syllabus. Example problems are solved to illustrate the given concepts.

### Evaluation method

The continuous assessment of the discipline is carried out through 2 tests, each worthing 35% of the final grade and exercises in the class in groups that worth 30% of the final grade.

The exercises are 3: 1st- chapter 1- 5%, 2nd- chapter 4- 10% and 3rd- chapter 5- 15%.

The first test covers the material in chapters  2 and 3 of the course syllabus. The second test covers the material given in chapters 6 and 7.

The duration of the tests is 1h. Each test is evaluated from 0 to 20 values. The assessment is individual and without consultation. A minimum classification of 10 (9.5) values ​​is required, on a scale from 0 to 20, in the average of the test scores and exercises.

If the student does not pass the continuous assessment or chooses not to do so, he/she will be entitled to an appeal exam. A minimum classification of 10 (9.5) values, on a scale from 0 to 20, is required in the exam grade and exercises for approval in the discipline. The final grade will be 70% of the mark on the exam and 30% of the grade for the exercises.

## Subject matter

1. Fundamentals of mass transfer. Definitions of concentrations, velocity and flux; Fick’s first law. Nernst-Planck equation. Diffusion coefficients; Methods for estimating diffusion coefficients. Diffusion of ionic species. Multicomponent diffusion.
2. Differential equations of mass transfer. Boundary conditions. Steady state molecular diffusion; Diffusion through a stagnant film; Equimolal counterdiffusion;
3. Diffusion with heterogeneous chemical reaction. Pseudo steady state diffusion.
4. Unsteady state molecular diffusion. Stefan-Maxwell equations. Analytical solutions of Fick’s secondlaw.
5. Convective mass transfer; Dimensional Analysis; Concentration boundary layer; Models and analogies of Reynolds and Chilton-Colburn; Empirical correlations.
6. Interphase mass transfer; Equilibrium gas- liquid and liquid- liquid; Two-resistance theory; Overall and individual mass transfer coefficients.
7. Diffusion with homogeneous chemical reaction; Hatta number; First and second order reactions.

## Programs

Programs where the course is taught: