# 31392 - Applied Thermodynamics

### Course Unit Page

• Teacher Michele Celli

• Credits 6

• SSD ING-IND/10

• Language Italian

• Campus of Bologna

• Degree Programme First cycle degree programme (L) in Energy Engineering (cod. 0924)

• Course Timetable from Sep 21, 2021 to Dec 21, 2021

### SDGs

This teaching activity contributes to the achievement of the Sustainable Development Goals of the UN 2030 Agenda.   ## Learning outcomes

The aim of the Course is to provide a clear and rigorous knowledge of the foundations of thermodynamics, of energy and entropy balances for a control volume, of the thermodynamic properties of pure substances and mixtures, of the principal thermodymanic cycles. This knowledge is a conceptual basis for the study of energy-conversion and energy-transfer systems, as well as of thermal-control and igrometric-control units.

## Course contents

Foundations of thermodynamics

The aim of thermodynamics. Basic definitions. Zeroth law and empirical temperature. First law and definition of property energy. Heat interaction. Energy balance for a closed system. Schematization of processes, thermal reservoir. Second law: Kelvin-Planck and Clausius statements. Definition of thermodynamic temperature. Clausius inequality. Definition of property entropy. Principle of entropy nondecrease. Highest entropy principle. Entropy flux and entropy production. Simple system. Internal energy. Fundamental relation. Gibbs equation. Phase rule. Closed simple systems: enthalpy, specific heat capacities, Helmoltz free energy, Gibbs free energy, Maxwell relations. Heat engines and refrigeration units between two thermal reservoirs.

Energy and entropy balance for a control volume

Quasi-simple system. Hypothesis of local thermodynamic equilibrium. Energy and entropy balance for a control volume. Combined balance and flow availability. Examples.

Properties of pure substances

State equation and diagrams [p.T], [p,v]. Ideal gases: equation of state and deduction of Joule's law; changes of internal energy, of enthalpy, of entropy; values of specific heat capacities. Properties of liquids. Properties of saturated vapours. Clapeyron equation. Properties of real gases. Diagrams [T,s], [h.s], [p.h].

Properties of mixtures

Properties of ideal-gas mixtures. Mixing entropy. Mixtures of air and water-vapour: humidity ratio and relative humidity, enthalpy versus humidity-ratio diagram, mixing of two streams of moist air, psychrometric chart.

Thermodynamic cycles

Rankine cycle. Refrigeration cycle.

The learning material is in Italian.

The learning material for the theory is given by the notes prepared by the teacher available online at the website:

https://virtuale.unibo.it

The exercises required for the exam are presented and solved by the teacher in classroom. Students can find the more exercises in the textbook

S. LAZZARI, B. PULVIRENTI, E. ROSSI DI SCHIO: “Esercizi risolti di Termodinamica, Moto dei Fluidi e Termocinetica” (Esculapio, Bologna, 2006).

## Teaching methods

The main teaching method is given by lectures presented in classroom by the teacher, that cover all the program, for theory and for exercises. Lectures are presented by employing a virtual backboard, with the aid of slides.

## Assessment methods

The exam consists of a test to be carried out, depending on the pandemic evolution, by employing EOL application or a in-class written test.

The exam is a multiple choice test focused on the evaluation of both the theoretical knowledge and the ability of solving exercises. There are 8 theoretical questions where every correct answer is worth 2 points, each incorrect answer is -0.5 points, each answer left blank is worth 0 points. There are also 3 exercises to be solved, for which each correct answer is worth 6 points, each incorrect answer is -1.5 points, each answer left blank is worth 0 points. The mark on the written test can be: insufficient ("ns") if the total score is less than 18; sufficient if the total score greater than or equal to 18, 30 cum laude ("30L") if all the 11 questions have been answered correctly.

The test, if the mark is greater/equal 18, allows one to record the exam. Students who wish to improve their marks can retake the test. Every time the student participate to a written test, the mark obtained before will be erased

In order to record the mark of "THERMODYNAMICS, FLUID MOTION AND HEAT TRANSFER T (I.C.)", the mark obtained for "APPLIED THERMODYNAMICS T" expires after 12 months. After this deadline the student has to repeat the exam. Both the professors of "APPLIED THERMODYNAMICS T" and "FLUID MOTION AND HEAT TRANSFER T" can record the mark.

The mark of "THERMODYNAMICS, FLUID MOTION AND HEAT TRANSFER T (I.C.)" is obtained by applying the arithmetic mean of the marks obtained by the student for "APPLIED THERMODYNAMICS T" and "FLUID MOTION AND HEAT TRANSFER T".

MARK RECORDING: from the moment of publication of the test results on Almaesami, students have 3 days to refuse the mark (by sending an email with the explicit request to michele.celli3@unibo.it). The refusal of the mark cancels the result of the test. The mark recording occurs automatically, it is not necessary for the student to do anything, after the 3 days. The mark recording will be carried out only if the student has obtained the marks of both "APPLIED THERMODYNAMICS T" and "FLUID MOTION AND HEAT TRANSFER T".

## Teaching tools

Lecture notes and exercises available on

https://virtuale.unibo.it

Video recording of the lectures available on STREAM - Microsoft 365

## Office hours

See the website of Michele Celli