LEARNING OUTCOMES

The course introduces the fundamental mechanisms of heat transfer (conduction, convection and thermal radiation) and shows some examples of practical application. The student will demonstrate a deep knowledge of the different heat transfer mechanisms and to be able to apply the fundamental laws to simple engineering problems. The goal of this course is to provide to the student the basis for the thermal analysis of energy transformation and production processes.

AIMS AND LEARNING OUTCOMES

At the end of course the student is expected to be able to:

• understand engineering problems related to the heat transfer;
• apply basic laws and models to the solution of simple heat transfer problems.

TEACHING METHODS

Lectures

SYLLABUS/CONTENT

HEAT CONDUCTION: General heat conduction equation; boundary and initial conditions; the thermal resistance approach; critical radius of insulation; heat transfer from finned surfaces; lumped system analysis; transient heat conduction in semi-infinite solids; finite difference formulation of differential equations in heat conduction.

HEAT CONVECTION: Fundamentals and preliminary analysis; conservation of mass equation; conservation of momentum equations: newtonian fluids and Navier-Stokes equations; conservation of energy equation; dimensionless forced convection equations and similarity; analogies between momentum and heat transfer; turbulence; Blasius solutions of convection equations for a flat plate; forced convection in tubes; natural convection: Boussinesq assumption; dimensionless natural convection equations.

THERMAL RADIATION: Fundamentals; blackbody and gray surfaces radiation; radiation heat transfer: black surfaces and diffuse, gray surfaces.

HEAT EXCHANGERS: Classification; the log mean temperature difference method; the effectiveness–NTU method.

TWO-PHASE HEAT TRANSFER: Fundamentals of pool and flow boiling; Nusselt equation for condensation.

This unit contributes to the achievement of the following Sustainable Development Goals of the UN 2030 Agenda: 4. Quality Education, 7. Clean and Affordable Energy, 9. Enterprise, innovation and infrastructure, 11. Sustainable cities and communities, 13. Fighting climate change.

RECOMMENDED READING/BIBLIOGRAPHY

• Y. Cengel. Heat and Mass Transfer, Ed. McGrawHill, 2015.

• Incropera, DeWitt, Bergman, Lavine: Fundamentals of Heat and Mass Transfer, John Wiley and Sons, 2011
• A.Bejan, Heat Transfer, John Wiley and Sons, Inc, 1993