Thermodynamics, Thermodynamic systems First and Second Principles Psychrometry Thermodynamic transformations of humid air and environmental conditioning Examples of thermodynamic cycles for winter and summer conditioning systems Heat transmission, stationary and transient regimes and periodic stabilization Conduction, convection (natural and forced), irradiation Mass and Energy Exchanges, Internal Energy, Enthalpy, Entropy, Exergy
1) Romagnoni P., Peron F., Vio M., Elementi di Fisica Tecnica Ambientale, CEDAM, Padova
2) De Santoli L., Fisica Tecnica Ambientale-Trasmissione del calore, C.E.A. , Milano, 1999
3) F. Kreith – Principi di Trasmissione del Calore – ed. Liguori.
4) Y. Cengel – Termodinamica e trasmissione del calore – McGraw-Hill
5) G. Guglielimini, C. Pisoni – Elementi di trasmissione del calore – Ed. Veschi.
Learning Objectives
To introduce the fundamental topics of thermodynamics and heat transmission for the understanding of systems (building and plant), of processes useful for achieving thermo-hygrometric well-being, air quality in a confined environment, hygiene and safety with particular reference to those of winter and summer air conditioning, ventilation and filtration (purity) of the air in the environment; to acquire suitable methods and tools for the energy-sustainable building-plant system project considering the physical quantities and the processes that characterize it by tackling the design aspects related to the themes of the building's thermo-physics, air-conditioning and the rational use of energy resources.
Prerequisites
Fundamental of algebra. Partial, differential and integral derivatives. Homogeneous differential equations, series expansion. Double integrals knowledge, surface calculation Coordinated knowledge of various types.
Fundamentals of chemistry
Teaching Methods
Lessons and practical tests
Further information
The exam consists of a written test. Who has not obtained the good enough result must support a different written test in any future session, by re-presenting themselves at any future examination session. It is always necessary to subscribe to the exam list provided for "TECHNICAL PHYSICS", in order to obtain the digital report and then the electronic verbalization. Please note that the examination of Technical Physics can be recorded ONLY as a weighted average on the number of CFUs together of General Physics, which must therefore be already supported and passed with a positive vote.
Type of Assessment
The exam aims to verify, through theoretical questions, and specific and targeted exercises:
- the knowledge of the fundamental topics and laws of thermodynamics;
-the knowledge of the fundamental issues and laws of thermal heat transfer and phase changes;
- the ability for an appropriately use of the terminology and methods of analysis of Technical Physics;
- the ability to understand the literature concerning the different methodological approaches to the analysis of closed and open thermodynamic systems;
- the ability to acquire the tools and methods to continue and develop the studies on the subject, knowing how to face and solve the related problems and to frame the issues and problems that are typical and crucial for all the Engineering sectors.
The exam consists of a written test. Who has not obtained the good enough result must support a different written test in any future session, by re-presenting themselves at any future examination session. It is always necessary to subscribe to the exam list provided for "TECHNICAL PHYSICS", in order to obtain the digital report and then the electronic verbalization. Please note that the examination of Technical Physics can be recorded ONLY as a weighted average on the number of CFUs together of General Physics, which must therefore be already supported and passed with a positive vote.
The exam aims to verify, through theoretical questions, and specific and targeted exercises:
- the knowledge of the fundamental topics and laws of thermodynamics;
-the knowledge of the fundamental issues and laws of thermal heat transfer and phase changes;
- the ability for an appropriately use of the terminology and methods of analysis of Technical Physics;
- the ability to understand the literature concerning the different methodological approaches to the analysis of closed and open thermodynamic systems;
- the ability to acquire the tools and methods to continue and develop the studies on the subject, knowing how to face and solve the related problems and to frame the issues and problems that are typical and crucial for all the Engineering sectors.
Course program
THERMODYNAMICS
the Open and Closed thermodynamic system
First and Second Principles of Thermodynamics - Principle of Carnot - Thermodynamic temperature
Thermodynamic systems, status and exchange quantities. Mass balances. First principle of thermodynamics for closed and open systems. Internal energy, enthalpy and specific heat. Conversion efficiency of direct cycles and efficiency of refrigeration and heat pump cycles. Statements of the second principle of thermodynamics.
Entropy concept and entropy analysis - Concept of exergy and exergetic analysis
psychrometrics
Ideal gases and pure substances
Ideal gases: equation of state; specific heats; evaluation of internal energy and enthalpy. Pure substances: state of aggregation of matter, phase transitions, definition of heat of vaporization / condensation.
Homogeneous Systems - Wet air - Thermodynamic transformations of humid air and environmental conditioning
Thermodynamic properties of moist air, psychrometric diagrams, technical transformations of moist air.
Examples of thermodynamic cycles of winter and summer air-conditioning systems and mixed air-water systems
Thermo-hygrometric wellbeing concept and environmental thermal loads
HEAT TRANSFER IN STATIONARY CONDITIONS
CONDUCTION: Fourier law - General conduction equation - Stationary conduction - Stationary monodimensional conduction without heat generation: flat, cylindrical and spherical walls with constant or variable thermal conductivity with temperature - Flat, cylindrical and spherical composite walls with thermal conductivity constant - Electrical analogy - Global heat exchange coefficient for flat and cylindrical geometries - Critical thickness of an insulation material - Stationary monodimensional conduction with heat generation
CONVECTION: forced convection, natural and mixed - Numbers of Nusselt, Prandtl and Grashof - Basic equations of non-isothermal motion - Dimensional analysis.
RADIATIVE HEAT EXCHANGE: Thermal Radiation and Light Radiation - Fundamental quantities: monochromatic, angular and integral emission power - Laws of irradiation: of Lambert, of Planck, of Wien, of Stefan-Boltzmann - Coefficients of reflection, transmission and absorption - Black bodies - Bodies grays and real bodies - Emissivity - Kirchoff's law - Radiosity - Factors of sight - Relationships between the factors of view: of reciprocity, of additivity and of closure - Heat exchange between black surfaces - Heat exchange between gray surfaces.
HEAT TRANSFER IN TRANSIENT CONDITIONS
Study of systems with concentrated parameters (systems with negligible internal resistance) - Thermal conduction in variable regime in flat surfaces - Introduction to numerical methods of solution of the heat exchange equation in transient conditions.