31006 - Environmental Technical Physics

Learning outcomes

The aim of the course is to give a basic knowledge of classical thermodynamics and heat transfer.
Basic information for study of simple thermodynamic systems, different kind of diagrams, some basic cycles, the properties of atmospheric air and its transformations applied to HVAC systems will be given.
Basic knowledge of heat transfer will be given: conduction, convection and radiation. Heat transfer and energy conversion problems will be studied.

Course contents

Requirements/Prior knowledge

A prior knowledge and understanding of Mathematical analysis (differential and integral calculus) and the basics of Physics are required to attend with profit this course. Fluent spoken and written Italian is a necessary pre-requisite: all lectures and tutorials, and all study material will be in Italian.

 

Course Contents

PART 1: THERMODYNAMICS

Introduction.
Introduction to Thermodynamics. System of units.
Principle zero of Thermodynamics. Thermometry.

First and second principle.
First principle of Thermodynamics for closed systems.
Second principle of Thermodynamics for closed systems:
statement by Kelvin-Planck, Clausius and their equivalence.
The Carnot machine.
Irreversibility of natural phenomena.
Entropy and lost work. Thermodynamic temperature.

Open systems.
Mass balance for open systems.
Energy balance for open systems.
Practical examples.
Pressure drop.

Pure substances, diagrams and cycles.
p-v-T surface for pure substances. The Gibbs rule.
Saturated vapours. Thermodynamic diagrams. Thermodynamic cycles. Ideal gases.

Air and vapour mixtures.
Description of air and vapour mixtures.
Psychrometric transformations.
Basics of environmental control.
Measurement of relative humidity.


PART 2: HEAT TRANSFER

Conduction.
Fourier law. Fourier equation.
Steady state solutions: plane layer, cylindric layer.
Critical radius.
Electric analogy and its limits.
Thermal resistances.

Convection.
Coefficient of convection.
Dimensional analysis and similarity.
Forced, natural and mixed convection.
Cooling by natural convection.
Dynamic and thermal boundary layer.

Radiation.
Basic definitions. Black and grey bodies.
Laws of Stefan-Boltzmann, Planck, Wien, Lambert, Kirchhoff.
Energy exchange between surfaces.

 

PART 3: BASIC NOTIONS OF ACOUSTICS

Physical acoustics, sound levels, decibel scale. Basics of frequency analysis, human hearing system, microphones e sound level meters, sound propagation.

Readings/Bibliography

Y.A. Çengel, Termodinamica e trasmissione del calore, McGraw-Hill, 2a Ed., Milano.

Teaching methods

All the contents of the course will be treated during classes. Numerical exercises will complement the classes.

 

A laboratory, on the practical application and experimentation of the topics discussed in the lessons using the Arduino system, will be organized. The laboratory will be held partially outside of the lesson hours. Active participation in this laboratory can contribute to the definition of the final grade of the course.

Assessment methods

Achievements will be assessed by the means of a final exam. This is based on an analytical assessment of the "expected learning outcomes" described above.

In order to properly assess such achievement, the examination is composed of different sections; a written session (optional), which consist of a 2-hour written test to be carried out without the help of notes or books and an oral test. The written exam consists of 10 questions, usually 5 questions of theory and 5 exercises. The written test, if sufficient, may replace the oral test, obtaining the maximum grade (30). An insufficient vote does not preclude the access to the oral examination. The written test can be carried out online

The oral examination consists of a discussion with the teacher, which aims to ensure the candidate's maturity and the possession of the knowledge and skills that characterize the subject. Short and simple exercises may be asked during the oral test. If the written test was sufficient, the oral examination can also be done to improve the score obtained in the written test.

Higher grades will be awarded to students who demonstrate an organic understanding of the subject, an high ability for critical application and a clear and concise presentation of the contents, in particular the first and second principles of thermodynamics, energy balances in closed and open systems, perfect gas laws and different heat transmission modes.

To obtain a passing grade, students are required to at least demonstrate a knowledge of the key concepts of the subject and a comprehensible use of technical language.

A failing grade will be awarded if the student shows knowledge gaps in key-concepts of the subject, inappropriate use of language, logic failures in the analysis of the subject or insufficient ability to understand the physical phenomenon represented by the formulas shown during the lessons.

 

Individual execution of the experiments assigned during the Arduino laboratory and their presentation to the teacher will bring to the student "bonus" points to be added to the final grade obtained in the manner described above.

Teaching tools

PC projector, overhead projector, other devices for streaming.
Course slides will be available for the students.

Links to further information

http://acustica.ing.unibo.it/Staff/paolo/courses-thermod.html

Office hours

See the website of Paolo Guidorzi