Learning outcomes of the course unit
To introduce the students to the basic concepts of thermodynamics and fluid flow applied to the analysis of the transformation of energy (thermal and mechanical) and of the transfer of thermal energy.
Genral physics and Mathematics.
Course contents summary
Thermodynamics. Definitions: systems and properties. Units (SI). Closed and open systems. Forms of energy. First Law. Second law. Entropy. Irreversibility. Closed systems: conservation of mass, conservation of energy. Open systems: definitions, conservation of mass, conservation of energy, steady and transient processes. Properties of pure substances, equilibrium diagrams (p,v) (p,T). Incompressible substances and their properties. Vapours: quality and other properties. Ideal gas. Vapor power cycles: Rankine cycle, ideal cycle, reheat. Refrigeration vapour cycle. Coefficient of performance. Thermodynamic efficiency. Simple multicomponents systems. Ideal gases mixtures. Mixtures of air and water vapour. Specific umidity. Psicrometric diagram.
Fluid flow: Physical aspect of the fluid flow. Coefficient of viscosity. Laminar and turbulent flow. Boundary layer. Reynolds number. Fluid flow in pipes. Integral equations Energy bilance equation. Bernoulli equation. Friction losses. Velocity and mass flow rate measurements in fluids. Compressible fluids. Mach number.
Heat transfer: Conduction. Fourier law. Energy balance equation. Fourier equation. Steady state conduction. Electrical analogy. Convection. Dimensional analysis. Thermal boundary layer. Forced, natural and mixed convection. Thermal radiation. Definitions. Laws of thermal radiation: Plack's law, Stefan-Boltzmann law. View factor. Applicaions to thermal radiation heat transfer between black and grey surfaces. Overall heat transfer coefficient. Finned surfaces. Heat exchangers. Logaritmic mean temperature difference. fficiency of the heat exchanger.
In order to make the students develop an analytical and problem-solving skill, part of the course is focused on exercises where the conceptual principles find practical application.
A. COCCHI: "Elementi di termofisica generale e applicata", Società Ed. Esculapio, Bologna, 1990.
G. Cammarata: "Fisica Tecnica Ambientale", McGraw Ed.
Exam: Written and oral examination.