FISICA TECNICA M - Z

The course aims to provide knowledge:

- of thermodynamics, in the fundamental theoretical aspects and, above all, in its plant components,

- direct and inverse thermodynamic cycles and air conditioning systems;

- of the three fundamental possibilities for the description and characterization of the heat exchange in simple geometries and heat exchangers.

As these skills are preparatory to disciplines such as: Fluid Machines, Energetics and Energy Systems and Thermotechnical Systems.

The course is carried out through the lectures conducted by the teacher on the subjects.

Course program of TECHNICAL PHYSICS Degree course in Industrial Engineering Teacher (M-Z course): Prof. Ing. Luigi Cammarata Department of Electrical, Electronic and Computer Engineering Academic Year 2018-2019 General thermodynamics Thermodynamic system: closed, open and isolated systems, equilibrium state of a system, characteristics of a system; quantities of exchange: heat and work, state variables: internal energy, enthalpy, entropy, exergy: exergy balances, exergetic yields of compressors and turbines, exergetic efficiency for thermal exchange. Thermodynamic process: process definition: isobaric, isovolumic, isothermal, adiabatic, polytropic process; equation of state and equation of transformation, perfect gases: equation of state and relative transformation equations; real gases according to the Van der Walls model: compressibility factor and law of the corresponding states; lamination process, Joule-Thompson expansion. First principle of thermodynamics: energy balance equation for open systems in the first and second form for transient regime and stationary regime, energy balance equation for closed systems. Second law of thermodynamics: Enunciation of Clausius, of Kelvin-Plank and statement of Carnot; direct cycle and reverse cycle thermal machine, Carnot machine; entropy: equality and inequality of Clausius, entropy of perfect gases, isoentropic expansion and compression yields, multistage compressions; calculation of thermostatic properties for any substance.

Applied thermodynamics

Direct gas cycles: Cycles in internal combustion engines: Otto cycle, Diesel cycle, Sabathè cycle, cycles in gas turbine engines: ideal and real Brayton-Joule cycle with and without regeneration; reversible bithermic cycles (Stirling cycle and Ericson cycle), cycle in a turbojet propeller, cogeneration and combined systems.

Direct steam cycles: Rankine dry saturated steam cycle, Hirn cycle, cycles with double overheating, tapping cycles.

Reverse steam and gas cycles: steam compression mechanical refrigeration machines: simple steam compression and simple rolling refrigerator, double compression and double rolling refrigerator; absorption refrigeration machine, gas refrigerating machine, heat pump.

Moist air: characteristic quantities of humid air, Mollier psychrometric diagram, main transformations of moist air, evaporative tower, summer and winter conditioning.

Fluid

Newtonian fluids: physical properties, kinematic and dynamic viscosity, mass and surface forces, stress state, and Newton's constitutive equations.

Kinematics: motion regimes, flow rate and average speed, differential equations and mass balance integrals, vortex motion and motion with kinetic potential, current lines and trajectories, current function.

Dynamics: differential balance of momentum (Navier-Stokes equation, Euler equation), integral balance of momentum (equation of impulses), barotropic fluids: Helmholtz equation.

Conducted motion: laminar and turbulent regimes, Reynolds similitude principle, Fanning friction factor and Weisbach factor, dimensional analysis for the determination of the friction factor in turbulent regime, velocity profile and tangential stress in the cylindrical ducts; pressure losses distributed in laminar and turbulent conditions, losses due to localized resistances, conducted in series and in parallel, closed and open circuits.

Open flows: dynamic boundary layer, Prandtl boundary layer equations for fluids with constant properties in laminar and turbulent regime, similitude of velocity profiles within the dynamic boundary layer, width of the boundary layer thickness in laminar and turbulent regime, factor friction room of Fanning, calculation of the characteristics of the boundary layer.

Compressible fluids: compressibility, expansion, sound velocity and Mach number; stagnation state and isentropic critical state; isoentropic motion in the nozzles and diffusers: Hugoniot theorem; adiabatic motion in the ducts with a constant section: Fanno's theorem, adiabatic critical state. Isothermal motorbike.

Heat transmission

Conduction: general equation of conduction: differential equation of Laplace, Poisson and Fourier, temperature gradient in flat, cylindrical and spherical surfaces with and without internal heat generation, heat flux calculation: Fourier postulate; finned surfaces: thermal gradient and efficiency of a fin.

Convection: convective heat exchange, Newton's postulate, forced and natural convection in the external conduits and outflow, dimensionless groups characteristic of the forced and natural convention, dimensional analysis for the determination of the convective heat exchange coefficient, mixed thermal-convective-convective heat exchange: resistance and thermal transmittance.

Heat exchangers: shapes and types: heat exchangers with concentric tubes, tube bundles, tubes and coatings, cross flow heat exchangers; heat exchange in equicurrent and countercurrent; calculation of the thermal transmittance for an exchanger, design and verification of an exchanger: method of the logarithmic mean difference and method of the calculation of the efficiency of an exchanger.

Irradiation: characteristic quantities of thermal radiation, absorption coefficients, reflection and transparency, black bodies and gray bodies, radiative emission of black bodies: Lambert's law, Stefan-Boltzmann's law, Plank's law, Wien's law; radiative emission of gray bodies, radiative properties of material bodies, heat exchanges for radiation for black and gray bodies: emissivity and form factors, law of reciprocity between form factors.

Luigi Cammarata : Termodinamica Generale

Luigi Cammarata : Termodinamica Applicata

Luigi Cammarata : Termocinetica (Fluidodinamica)

Luigi Cammarata : Termocinetica (Trasmissione del calore)

Cavallini- Mattarolo : Termodinamica applicata (Cleup editore)

Guglielmini-Pisoni : Elementi di trasmissione del calore (editoriale Vaschi)

Alessandro Cocchi : Termofisica generale ed applicata (Progetto Leonardo)