The course has the following specific objectives: to give some fundamentals on heat transfer applied to energy transformation and production; to provide some general bases in the energetic field, in such a way the student can make correct options on the production and rational use of energy; to give the first elements on solar and nuclear energy.
Aims
Through the contents of the teaching, the student is able to analyze and solve simple problems in the different areas of heat transfer.
The lessons and activities aim at the same time to
Learning outcomes
At the end of the course, students will have to
Furthermore, as a desirable more advanced result, students will also be able to acquire an awareness of the subject so as to be able to analyse more complex problems relating to physical-technical applications in the field of mechanical engineering.
Teaching is conducted in Italian with a predominantly traditional teaching method, alternating frontal lessons with numerical exercises.
HEAT TRANSFER
One-dimensional steady-state thermal conduction: Fourier's law, thermal conductivity, thermal conduction in flat and cylindrical geometries, thermal resistance, multilayer flat walls, complex flat walls, multilayer cylindrical pipes. Multidimensional transient thermal conduction: Fourier's law, general equation of conduction, thermal bridges, thermal diffusivity, periodic steady state in a semi-infinite medium. Convective heat transfer: viscosity, coefficient of cubic expansion, Newton's law, convection coefficient. Forced convection on a flat plate and in a tube. Natural convection on a flat plate and in a cavity. Dimensionless numbers and solving problems of convective heat transfer. Radiative heat transfer: electromagnetic waves, black body, Planck's and Wien's laws, emissivity, gray body, irradiation, absorption, reflection, and transmission factors, Kirchhoff's law, selective surfaces, view factor, heat exchange between black and gray surfaces, emissivity coefficient. Combined mechanisms of heat transfer: heat exchange at a surface, critical heat transfer coefficient, multilayer and complex flat walls, heat transmittance. Heat transmittance of opaque elements of the building envelope and windows, thermal bridges, multilayer cylindrical pipes, sizing of a heating body. Introduction to combined mechanisms of transient heat transfer: thermal capacity, transient heat transfer of a thin body, transient heat transfer of a multilayer wall, periodic heat transmittance.
HVAC SYSTEMS AND PLANTS
Energy equation in mechanical terms. Bernoulli's equation. Distributed pressure losses. Concentrated pressure losses. Pump pressure head. Converging and diverging channels. Pump and turbine efficiency, closed circuit.
Classification of air conditioning systems. Mass and energy balance of a conditioned environment. Heating system: losses due to ventilation and transmission, sizing and calculation parameters.
FUNDAMENTALS OF ENERGETICS
Primary energy sources and renewable sources. Reminders on world and national energy panorama relating to energy consumption and production. Nuclear energy. Notes on the impact of the energy sources.
Texts and notes distributed or suggested during class by the teacher.
Ricevimento: By appointment: guglielmo.lomonaco@unige.it
https://corsi.unige.it/en/corsi/8784/studenti-orario
At the end of the classes, only those who have passed the first module (72371 – Modulo di Termodinamica Applicata) are eligible to take the partial written and oral exam on the module's curriculum. This opportunity is limited to the summer session exams (May-July). In case of failure to pass the partial exam, the student will be required to take the written and oral exam on the entire course curriculum. As for the exam procedures for the partial exams, the ones specified for the final exam apply (see sheet 72369 – Fisica Tecnica).
As for the evaluation of partial exams, the same criteria specified for the final exam apply (see sheet 72369 – Fisica Tecnica).
