ΠΕΡΙΓΡΑΜΜΑ ΜΑΘΗΜΑΤΟΣ

The course aims to achieve the following learning outcomes for students:

• acquiring knowledge in the basic engineering principles that govern the physical processes during food processing
• recognizing, understanding and interpreting the physical phenomena govern these processes
• the ability to describe mathematically and evaluate the contribution of each phenomenon or parameter to the evolution of the process
• acquiring experience in applying the above knowledge and analytical skills to industrial-scale processes

• Analyzing, interpreting and synthesizing empirical data obtained from experimental setups
• Searching and analyzing information using information and communication technologies
• Promotion of analytical, productive and inductive thinking
• Working in an interdisciplinary environment
• Autonomous work
• Teamwork
• Decision making

Unit 1: Mass and Energy Balances

• The concept of balance on steady-state or transient system. The principles of mass and energy conservation.
• Formulation and solution of mass balances in simple and complex processes with or without reactions.
• Phase diagrams and phase equilibria. Gibbs rule.
• Humidity and psychometric charts.
• Internal energy, enthalpy, heat and work. Steam tables. Energy balances.

Unit 2: Fluid Mechanics

• Hydrostatic equilibrium. Absolute and manometric pressure
• Flow phenomena. Viscosity and Newton’s law. Types of rheological behavior. Laminar and turbulent flow, Reynolds number. Boundary layers in walls.
• Flow equations. Average velocity, momentum and energy in unidirectional flow. Continuity, momentum and mechanical energy (Bernoulli) equations. Flow from orifice.
• Incompressible flow in pipes. Wall friction, friction coefficient Fanning. Non-circular pipes. Velocity profiles in laminar and turbulent flow. Equation Hagen-Poiseuille. Calculation of friction coefficients in smooth and rough pipes. Friction due to cross section reduction or enlargement and the presence of valves etc. Pump power.
• Types and categories of pressure, flow and tank level sensors.

Unit 3: Heat Transfer

• Heat transfer mechanisms. Conduction and Fourier’s law. Thermal conductivity. Convection, Newton’ law. Heat transfer coefficients.
• Steady-state Conduction. Unidirectional conduction in planar, cylindrical and spherical geometry. Conduction through multiple layers. Combined conduction-convection in fluids.
• Non-steady-state Conduction. The Biot number. Thermal Diffusivity. The Fourier Number. Lumped capacity analysis. Charts for transient heating/cooling in planar, cylindrical, spherical and complex geometries.
• Forced Convection. The Nusselt and Prandtl numbers. Thermal boundary layer. Heat transfer equations for laminar and turbulent flow over slabs and through pipes. Natural convection. The Grashof number. Convection with phase change: condensation and evaporation.
• Heat transfer devices: heat exchangers and their types. Heat transfer equation for double-pipe heat exchangers. Correction factor for composite heat exchangers. NTU method. Heated tanks: calculation of heating/cooling time.
• Types and categories of temperature sensors. Steam networks and steam traps.

Titles of Laboratory Exercises

• Non-steady state heating of a can
• Flow meters – Pressure drop
• Heat exchangers
• Spray Dryer

Συγγράμματα

1. McCabe W., Smith J., Harriott P., Βασικές Φυσικές Διεργασίες Μηχανικής, 6η Έκδοση, Μετάφραση: Εκδόσεις Τζιόλα, Θεσσαλονίκη, 2003.
2. Pitts D., Sissom L., Μεταφορά Θερμότητας, Σειρά Schaum, 2η Έκδοση, Μετάφραση: Εκδόσεις Τζιόλα, Θεσσαλονίκη, 2001.
3. Himmelblau D.M., Riggs J.B., Βασικές Αρχές και Υπολογισμοί στη Χημική Μηχανική, 7η Έκδοση, Μετάφραση: Εκδόσεις Τζιόλα, Θεσσαλονίκη, 2006.
4. Fryer P.J, Pyle, D.L., Reilly C.D., Chemical Engineering for the Food Industry, Chapman & Hall, 1997.

Συναφή επιστημονικά περιοδικά

1. Journal of Food Engineering.
2. Journal of Food Processing & Technology.