# Ingegneria Alimentare - Food Engineering | TRANSPORT PHENOMENA IN FOOD PROCESSES

## Ingegneria Alimentare - Food Engineering TRANSPORT PHENOMENA IN FOOD PROCESSES

 0622800020 DIPARTIMENTO DI INGEGNERIA INDUSTRIALE EQF7 FOOD ENGINEERING 2022/2023

 OBBLIGATORIO YEAR OF COURSE 1 YEAR OF DIDACTIC SYSTEM 2019 SPRING SEMESTER
SSD CFU HOURS ACTIVITY TYPE OF ACTIVITY ING-IND/24 9 90 LESSONS COMPULSORY SUBJECTS, CHARACTERISTIC OF THE CLASS
 GAETANO LAMBERTI T FRANCESCO MARRA
Objectives
Knowledge and understanding:
Generalized balance equations and field equations. Microscopic (differential) and macroscopic (integral) balances. Euler and Lagrange forms of balance equations. Continuity, momentum, mechanical energy, thermal energy, single specie balance equations. Approach to problem resolution; Summary of balance equations. Scale up methods based on dimensional analysis and similarities: dimensional analysis of balance equation; dimensionless numbers. Transport with more than one independent variables. Small-time approximations: the penetration theory; stream and potential functions. Turbulent fluxes and diffusivities. Empirical expressions for turbulent fluxes: eddy viscosity, mixing length, profiles near a wall, turbulence in ducts and jets, the kappa-epsilon models. Boundary layer theory. Interphase transport coefficients. Flow in ducts, transport phenomena with phase change, transport phenomena with chemical reactions; Rheology and rheometry: newtonian and non-newtonian fluids, viscoelasticity. Measurements of engineering properties of food materials.

Applying knowledge and understanding – engineering analysis
Ability to properly apply and adapt the equations of change with respect to specific applications to food processes.

Applying knowledge and understanding – engineering design
Ability to solve properly equation of changes in applications to food processes.

Making judgments - engineering practice:
Make use of the results of specific transport property measurements to predict the behavior of food materials.

Communication skills – transversal skills:
The student will be able to present, in a concise way, the most relevant aspects of a transport phenomena problem in food processes, from mathematical description of phenomena, to discussion of initial and boundary conditions, up to solution forms. The acquired communication skills will allow the student to interact with other professionals of different background, from food technologists and food scientists to production managers.

Learning skills – transversal skills:
Knowing how to apply their knowledge to different contexts from those presented during the course.
Prerequisites
Knowledge of basic thermodynamics and mathematics is required. The basics of transport phenomena, even if useful, will be summarized during the course.
Contents
Introduction to transport phenomena in food industries (TPs) (6h the, 4h exe)
Definition and meanings of TPs - general framework of TPs - general rate equation (GRE) - simple experiments and definitions of transport properties - molecular fluxes - convective fluxes - combined fluxes - transport properties: methods of measurements - modeling and predictions

Balance equations (BEs) or field equations (FEs) (6h the, 4h exe)
Generalized balance equation (GBE) - balances: microscopic (differential) and macroscopic (integral) - Euler and Lagrange forms of BEs - continuity, momentum, mechanical energy, thermal energy, single specie BES - solving problem approach for food processes - summary of BEs.

Dimensional analysis (DA) and similarities (6h the, 6h exe)
Introduction to DA - Buckingham "pi" theorem, Buckingham and Raleigh’s methods - similarities - dimensional analysis of BEs - dimensionless numbers: list, meanings, applications - scale-up basics

Transport with more than one independent variables in food processes (10h the, 6h exe)
Transient transport phenomena – small-time approximations (the penetration theory) - stream functions - potential functions

Turbulence and boundary layer in food processes (8h the, 6h exe)
Turbulent flow – time-smoothed BEs – turbulent fluxes and diffusivities – Impingement jets in food processes. Entrance problems for food flow in conducts - Heat and mass transfer around submerged objects – interphase transport coefficients for food processes,

Rheology and rheometry (6h the, 4h exe)
Introduction to rheology - viscosity: definition, dependencies, Newtonian and non-Newtonian fluids, viscosity measurements - viscoelasticity: definition, mechanical models, constitutive equations, dynamic testing

Applications (8h the, 10h exe)
Momentum transport in food processes - transport phenomena with phase change: food thawing - transport phenomena with chemical reactions in food processes - measurements of engineering properties of foodstuff - simultaneous heat and mass transfer in solid foods: transfer toward the food, transfer from the food. Reactant systems in food processes.
Teaching Methods
THE COURSE CONSISTS IN FRONT LESSONS (50H) AND CLASSROOM EXERCISES (40H) FOR A TOTAL AMOUNT OF 90 HOURS WHICH ARE WORTH 9 CREDITS. BOTH LECTURES AND EXERCISES CONSIDER APPLICATION TO THE SOLUTION OF REAL LIFE PROBLEMS.
FOR SOME EXERCISES WE WILL USE SPREADSHEETS AND SOFTWARES TO SOLVE PARTIAL DIFFERENTIAL EQUATIONS (PDES) AND FOR THE SIMULATIONS OF TRANSPORT PHENOMENA.
ATTENDANCE AT THE LECTURES IS STRONGLY RECOMMENDED.
Verification of learning
The learning assessment process requires a written test and an oral test. The written test has a duration of two hours, it is an open-book test, the candidate can make use of whatever he/she wants (no internet), and the test is made by two exercises, each one with three questions. For each question there is a grade (5 points on average), and these points are given entirely if the answer is correct even from numerical point of view, at 80% if there is a calculation mistake, from 10% to 70% if the answer is given but conceptual errors are present (zero if the answer is absent or seriously flawed). The oral test is made by a single question on a topic analyzed during the course; the average duration starts from twenty minutes (if the answers are given rapidly and correctly), up to one hour if the candidate is not sure in his/her answers and takes time to give the answers. The sufficiency is obtained if the candidate demonstrates the ability to select the methods to be used, to write correctly the model equations and at least to select the correct path to their solution. The excellence is obtained when the candidate is able to face out successfully even aspects of the topic not analyzed during the course. The final grade depends from the level of exposition and from the confidence shown with the course’s topics, and with the methods, the uses of which have been shown during the course.
Texts
[1] R. B. Bird, W. E. Stewart, E. N. Lightfoot, "Transport Phenomena", 2nd Edition, John Wiley & Sons, New York, 2002.
further suggested sources
[2] R. S. Brodkey, H. C. Hershey, "Transport Phenomena: a Unified Approach", Brodkey Publishing, Columbus, Ohio, 2001 (Formerly: John Wiley & Sons, New York, 1988).
[3] I. Tosun, "Modeling in Transport Phenomena: a Conceptual Approach", 2nd Edition, Elsevier Science, Amsterdam, 2007.
[4] M. Zlokarnik, "Scale-Up in Chemical Engineering", Wiley-Vch Verlag Gmbh & Co., Weinheim, 2002.
[5] A. Ibarz, G. V. Barbosa-Cánovas, "Unit Operations in Food Engineering", Crc, Boca Raton, 2003.
Course webpage
http://gruppotpp.unisa.it/en/transport-phenomena-in-food-processes/