00430 - Technical Physics

Learning outcomes

At the end of the course the student is able to: - Know the energy conversion and control systems, - Know the basic principles of thermodynamics, - Know how to perform energy balances for the most basic processes of technological interest.

Course contents

• Applied thermodynamics (about 15 hours)

  • Thermodynamics applied to closed systems: definition of system and environment, closed system, open system, isolated system, properties and state, process and cycle, state of thermodynamic equilibrium, thermal equilibrium, temperature scales, extensive, intensive, specific properties, definition of work and heat, first law of thermodynamics, adiabatic process, enthalpy, examples and exercises.
  • Thermodynamics applied to open systems: control volume, energy of a mass of fluid in motion, energy balance for open systems in steady state, examples: boiler and condenser, turbine and compressor, valves, nozzles, exercises.
  • Single-component thermodynamic systems: definition of phase, phase rule and examples, specific heat capacity at constant volume, specific heat capacity at constant pressure, equation of state for perfect gases, Joule's law, Joule's experiment, specific enthalpy of an ideal gas, examples and exercises.
  • Perfect gas mixtures: Dalton's law, humid air, absolute humidity and relative humidity of the air, enthalpy of humid air, dew temperature, dry bulb and wet bulb temperature, psychrometric diagram, examples and exercises.

  Fluid mechanics (about 9 hours)

  • Fluidostatics: pressure, Pascal's principle, Stevin's law and consequences, U manometer, Archimedes' principle, examples and exercises.
  • Fluid dynamics: volume flow and mass flow, continuity equation, Bernoulli equation and applications, real fluids and viscosity, Reynolds number, laminar and turbulent flow, distributed and concentrated pressure drops, Moody's diagram, examples and exercises.

  Heat transfer (about 12 hours)

  • Conduction: thermal conductivity, thermal power and thermal flux density, Fourier's law, thermal resistance by conduction, thermal resistances in series and in parallel, examples and exercises.
  • Convection: forced, natural and mixed convection, thermal power and convection coefficient, Nusselt number, thermal resistance by convection, examples and exercises.
  • Thermal radiation: opaque, transparent and black body, thermal power and emissivity, examples and exercises.

  Towards the end of the course there will be a visit to the Technical Physics Laboratory of the Industrial Engineering Department (via Terracini 34, Bologna), equipped with qualified equipment for measuring temperature, pressure, velocity in fluids, thermal conductivity of materials and for monitoring the environmental conditions within building rooms.

Readings/Bibliography

• Lecture notes by the professor. The handouts contain all the theoretical elements and the resolution of exercises necessary to sustain the exam. Students are invited to download the handouts from the repository https://virtuale.unibo.it/ using their University institutional credentials. Examples of questions from previous exams can also be downloaded from the Unibo repository.

  For any further information it is recommended to read:

  Y. A. Çengel, Termodinamica e Trasmissione del Calore, McGraw Hill, 2016

  S. Lazzari, B. Pulvirenti, E. Rossi di Schio, Esercizi di Termodinamica, Moto dei Fluidi e Trasmissione del Calore, Esculapio, 2006

Teaching methods

The course is based on lectures held in person at Plesso Didattico Vespignani (via Garibaldi 24, Imola), by means of which the theoretical contents will be exposed and exercises will be carried out with the aid of both the virtual and traditional whiteboard.

Assessment methods

Verification of learning involves the delivery of an in-depth essay on a topic of the course and the performance of a written test. The in-depth essay is carried out in small groups of 3-4 students and each topic is agreed in class with the teacher. Each group chooses the topic among a list proposed by the teacher.

During the written test, the student must demonstrate that he can answer theoretical questions and solve simple exercises similar to those carried out in class. The written test contains a series of multiple choice and open questions, concerning theoretical topics and the resolution of exercises. The questions will focus on all the macro-areas of training (applied thermodynamics, fluid mechanics, heat transfer).

60 minutes are allocated for the test. During the exam, the use of a calculator is required and books, handouts, notes and electronic devices cannot be consulted.

Sample questions from previous exam tests can be downloaded from the website https://virtuale.unibo.it/.

The student can consult the list of exam sessions and register on the AlmaEsami website https://almaesami.unibo.it/.

The mark of the written test may be: not sufficient (rejected) if the score is less than 18; sufficient if the score is between 18 and 30; 30 cum laude if the student has answered all the questions correctly. The mark resulting from the written test is increased by the points obtained in the in-depth paper (from a minimum of 0 to a maximum of 3 points) only if the mark of the written test is at least 18. For example, if the grade resulting from the written test is 20 and the points obtained through the thesis are 2, the final grade in Technical Physics is 22.

The student can take the written test again if the score obtained does not satisfy him, but every time he presents himself to a new exam and delivers the written test the previously obtained score loses all value, i.e. the most recent grade is considered, whatever it is the result obtained. Conversely, in the event of withdrawal during the new exam, the grade obtained previously is considered. The points obtained with the in-depth thesis remain valid.

The final grade of the integrated Physics course is given by the arithmetic average of the scores obtained in the Applied Physics and Technical Physics tests. The integrated Physics course is considered as sustained when a sufficient mark is obtained (greater than or equal to 18) in both courses (Applied Physics and Technical Physics).

The teachers of the individual courses of Applied Physics and Technical Physics publish the results obtained by the students for the individual courses directly on Almaesami in few days following the related exam tests. At the end of each exam session (beginning of March, end of July and end of September) the teachers will register the Integrated Physics Course to all students who have obtained a sufficient grade in both courses by making the arithmetic average of the marks obtained in the individual courses.

Students who, despite having obtained a sufficient grade for both courses, do not want to obtain the verbalization of the whole integrated Course (for example because they want to improve the scores obtained during single exams during future sessions), must send an email to both teachers to communicate them that they do not want to register the integrated Course immediately at the end of each exam session.

Teaching tools

Presentations with the aid of the PC, presentation of theoretical contents and resolution of exercises. Handouts provided by the teacher can be downloaded from https://virtuale.unibo.it/.

Please look at the teacher webpage for office huors.

Office hours

See the website of Matteo Dongellini