Learning outcomes of the course unit
The course develops the notions of Fluid mechanics, already introduced in the elementary courses of Physic, with particular reference to water in order to acquire the tools necessary for the analysis of the simple hydraulic systems useful for the advanced courses in hydrology and hydraulic structures.
Differential analysis AB and C, Geometry, General Physics AB.
Course contents summary
Fluids and fluid behavior. Definition of fluid as a continuum. REV concept. Fluid mechanics and units. Stresses in a continuum. Density and specific weight. Compressibility. Surface tension. Viscosity. Gas sorption. Vapor pressure of a fluid. Flow regimes.
Fluid statics. Internal stresses in fluids at rest. Differential analysis of luid statics. Finite control volume analysis of fluid statics. Pressure variation of incompressible fluids. Hydrostatic force on plane and curved surfaces. Fluids with low specific weight. Buoyancy. Pressure variation in a fluid with rigid-body motion.
Fluid kinematics. Velocity and acceleration fields. Pathlines, streamlines, streaklines. Continuity equation
Basic fluid dynamics. Differential and finite control volume analyses of a fluid flow. Euler equation.
The Bernoulli equation. Gradually varied flow. The Bernoulli equation. Physical and geometrical interpretation. Examples of the use of the Bernoulli equation. Viscous fluids. Extension of the use of the Bernoulli equation to streams. Energy exchanges between fluid and hydraulic machinery.
Flow of viscous fluids. Navier-Stokes equations. Finite control volume analysis.
Viscous flow in pipes. General characteristics of uniform flows. Laminar motion. Turbulent motion. Turbulent and viscous shear stresse. Colebrook equation and emprirical formulations. Concentrated head losses. Pipe flow hydraulic problems.
Open-channel flow. General characteristics. Uniform flow. Energy distribution in a cross section. Mild and steep channels. Kinematic characteristics of stream (subcritical and supercritical flows). Theoretical profiles of stationary flow. Critical flow transition. Hydraulic jump.
Introduction to flow through porous media.
Citrini D. e G. Noseda: Idraulica, Ed. Casa Ed. Ambrosiana, Milano.
Numerical practicals are developed on the following topics: computation of static forces on plane and curve surfaces; computation of dynamic forces of jets impacting on plates or stream in a curved conduit; hydraulic computation of pressure flow: design and check problems; flow circuits with pumps or turbines; computation of uniform and critical water level in channels.
Scientific film show.
Optional oral exam after written exam.