Provide basic methodology for setting the thermal energy balance of systems. Equation of heat and mass balance. Deepening of the main physical phenomena and definition of mathematical models that represent them. Knowledge of main air treatments in HVAC systems. Design of heating and domestic hot water system for residential users. The knowledge of the features characterizing the architectonic acoustics. Particular attention will be paid to the link between the studied physical phenomena and their applications in the field of energy conservation, the global welfare of the occupants. This course aims to provide the skills that form the basis for a conscious design to issues related to energy and the environment.
The course includes the alternation between theoretical lessons and practical exercises on the issues developed in the classroom.
If the teaching will be given in mixed or remote mode, the necessary changes to what was previously stated may be introduced, in order to comply with the program provided and reported in the syllabus
Fundamentals of Thermodynamics
a) The Thermodynamic System
International System of measurement units. Definitions and measurability of internal energy. The heat energy as a mode of exchange. The first principle of thermodynamics in expanded form.
b) state of equilibrium.
Magnitudes of physical condition and location. intensive and extensive quantities. Dependence of the work and the heat of the type of thermodynamic process. The entropic postulates. Reversible and irreversible processes. quasi-static transformations. Gibbs equation.
The second law of thermodynamics (Clausius and Kelvin).
c) The ideal gas
State equations. Specific heat at P and V constant. Transformations at T, P, V constant. adiabatic quasistatic. Entropy of an ideal gas. Notes on the behavior of real gases.
d) The diagrams of physical state.
The diagrams (P-T), (p-v), (t-s). Steam water. Major transformations of the water vapor.
Vapor title. The MOLLIER diagram (h-s) for the water vapor.
e) Direct and inverse cycles.
Cyclical Processes . Direct steam cycles (Rankine and Hirn), gas turbines and Joule Bryton cycles. The refrigerator cycle. isoentropic efficiency. absorption refrigeration cycles.
f) Moist air.
The fundamental values. psychometric diagrams for the humid air. The humid air transformations. temperature of saturation and dew point temperature. processes for summer and winter conditioning.
HEAT and hints of fluid dynamics
Bernoulli equation. Similitude, dimensional analysis and modeling. Internal and external flows. Fluid flow in the ducts. Reynolds number. Flow regimes of a liquid in a conduit.
(Regimes: laminar, turbulent and transitional). Friction factor. Coefficients of dynamic and kinematic viscosity. Profiles of velocity .
h) Heat transfer by conduction
The Fourier postulated. The energy balance in a steady state . The flat plate; the multilayer planar walls (with and without thermal power generation). Electric analogy. The energy balance in the case of cylindrical symmetry. Insulated pipe. electrical analogy. The critical radius. Unsteady conduction: Biot number; method of concentrated capacity.
i) Heat transfer by convection.
external flow and internal flow to the surface. boundary layer. the boundary layer assumptions.
l) Forced convection:
dimensionless groups for forced convection and
similarity. dimensionless groups for the natural convection.
experimental dimensionless correlations for the forced heat convection to the main
heat exchange configurations of outside and inside surfaces of conduits.
m) Natural convection:
General consideration. constitutive equations for natural convection. Hypothesis Boussinesque. Natural convection in open spaces.
n) heat transfer by radiation
Emissive power. Irradiation. monochrome and overall . The black body: laws of
Planck, Stefan-Boltzmann, Wien. The coefficients of absorption, reflection, transmission and emission. Kirchhoff's law. The gray body. heat exchange between blacks bodies: the form factor.
ENERGY AND TECHNICAL SYSTEMS
o) HEATING SYSTEM
Heat exchangers. Hydronic distribution networks. Pressure drops continuous and localized. Moody chart.
Darcy-Weisbach formula, Chézy, Colebrook, of Kutter and Darcy. Power of a machine
Operating hydraulic (pump). Calculation of the manometric prevalence and total of a pump. Characteristic curves. emission terminals. Hints on Control Systems
p) Elements of acoustics
Main acoustical parameters. Propagation of sound waves. Spectral analysis.