Degree in
"Construction Engineering" - L 23 - 2nd year
Program of the course of:
TECHNICAL PHYSICS CFU: 9 SSD: ING-IND / 11 A.A. 20018/19
Prof. Paolo ZAZZINI
Introduction
Measurement Units systems: fundamental and derived quantities, conversion factors, measurement of physical quantities, conversions between the various measurement units systems.
Thermodynamics
Open and closed thermodynamic systems, thermodynamic equilibrium, extensive and intensive properties, state and exchange physical properties.
Total energy and internal energy of a system, temperature, specific heat, thermal capacity of a thermodynamic system.
Balance of mass and energy, I Principle of Thermodynamics for closed and open systems, enthalpy of a system, pressure-volume diagram, isobar, isocore, isotherm, adiabatic and politropic processes.
II Principle of Thermodynamics: Clausius and Kelvin-Planck statements, thermodynamic cycles, the direct and inverse Carnot cycle, thermal and refrigeration machines, heat pumps, thermodynamic cycles: Rankine cycle and Brayton cycle, entropy, temperature-entropy diagram.
Pure substances, phase-changes, properties of vapors and liquids, pressure-temperature diagram, notable points, the triple point.
The perfect gases: I and II state law, internal energy and enthalpy of a perfect gas; thermodynamic transformations of perfect gases.
Moist air: thermodynamic properties, psychrometric diagram, heating and sensible cooling transformations, humidification and dehumidification, adiabatic mixing; dew temperature, wet bulb and adiabatic saturation temperature, the psychrometer.
Heat transfer
Fundamental heat transfer mechanisms: conduction, convection and radiation;
Thermal conduction: Fourier postulate, thermal conductivity.
One-dimensional stationary system: flat wall, cylindrical wall, conductance, resistance, temperature trend within a flat wall and in the thickness of a hollow cylinder; composite structures: multilayer flat wall, series and parallel resistances, coaxial cylinders, critical insulation thickness.
Thermal convection: Newton's law, average coefficient of convective heat exchange, natural convection and forced convection, laminar flow and turbulent flow, number of of Nusselt, Reynolds, Prandtl and Grashof.
Thermal radiation:
Radiant energy, the black body, emissive power, emission laws of the black body of Planck, Stephan-Boltzmann and Wien, radiative heat transfer equations for black bodies, gray bodies, emissivity, radiative balance equations for gray bodies , greenhouse effect; radiative heat transfer in cavities between black surfaces.
Combined heat transfer mechanisms for multilayer flat walls: thermal transmittance and thermal resistance of a wall, thermal behavior inside a multilayer wall; surface condensation, interstitial condensation, Glaser method.
