Transport phenomena II

Recommended Prerequisites

Calculus I, II and III, Transport Phenomena I, Chemical Thermodynamics, Mass and Energy Balances.

Teaching Methods

There are theoretical (T) and theoretical-practical (TP) lectures. In the first, theoretical concepts are presented followed by their applications through the presentation of case studies that are discussed and solved in class. The main way of teaching is in the form of handouts, using also small demonstration movies. Students are encouraged to solve exercises in TP class, where discussions with their colleagues are allowed. Some problems are also proposed for autonomous solving which are then discussed in following TP class.

Learning Outcomes

Besides the physical understanding, students should:
1. identify and mathematically describe the mechanisms of heat transfer;
2. understand the concept of thermal resistance, identifying the existence of thermal resistance in series and quantify the total resistance;
3. establish energy balances in steady state and in transient conditions;
4. know the methodology for calculating the heat transfer coefficients;
5. design equipment where heat transfer occurs with or without phase change (heat exchangers, condensers and evaporators).

The students should develop the ability to understand and relate knowledge of the contents taught, to acquire knowledge independently and to formulate and solve problems. They should also demonstrate a well-structured and integrated way of thinking by applying their knowledge and understanding in a manner that indicates a professional approach to their work.

Work Placement(s)

No

Syllabus

Heat transfer: mechanisms (conduction, free and forced convection, radiation), thermal resistances in series; overall heat transfer coefficient, thermal insulation, empirical correlations for heat transfer coefficients. Dimensional analysis. Internal and external flow (flow over spheres, cylinders and plates). Analogy between momentum and heat transfer. Unsteady-state heat transfer: heating/cooling in lumped systems; temperature variation with time and position (microscopic balances in plane walls, cylinders and spheres) – Heisler and Gurney-Lurie charts.

Heat transfer equipment: design and operation variables of heat exchangers, condensers and evaporators (single- and multiple-effect  with different feed position); correction factor for logarithmic mean temperature difference (LMTD); fowling factor; efficiency and NTU definition.

Head Lecturer(s)

Maria da Graça Videira de Sousa Carvalho

Assessment Methods

Continuous assessment
Frequency: 100.0%

Final assessment
Exam: 100.0%

Bibliography

- Bergman, T.L.; Lavine, A.S.; Incropera, F.P.; de Witt, D.P. Fundamentals of Heat and Mass Transfer. 7th ed, J. Wiley & Sons, N.Y., 2011.

- Çengel, Y.; A.Ghajar, A. Heat and Mass Transfer: Fundamentals and Applications. McGraw-Hill Inc., N.Y. , 2010.

- Geankoplis, C.J. Transport Processes and Separation Process (Includes Unit Operations), 4th ed., Prentice-Hall, 2003

- 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.

- Holman, J.P. Heat Transfer. 9th ed. , McGraw-Hill Inc., N.Y. , 2002.

- McCabe, W.; Smith, J.; Harriott, P. Unit Operations of Chemical Engineering. 7th ed. McGraw-Hill Book Co., NewYork, 2005.

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

- Datta, A.K. Biological and bioenvironmental heat and mass transfer, Marcel Dekker Inc., N.Y. 2002.