The course is aimed at providing the basic information for:
The choice of a fluid machine basing on the requested performance
The knowledge of its behaviour, and related fluid dynamic and structural issues
The course aims at providing the basic information about the functioning of compressors, fans, and pumps. The effects of the kind of fluid, and of structural and economic issues on the machine architecture are also considered. On such a basis, choice and installation criteria are derived, and information are provided about the machine operation, also considering the system in which the machine is installed. Preliminarily, physical properties of technical fluids are recalled, together with thermodynamic and fluid dynamic equations relevant to fluid machinery.
Theoretical and applied lectures
The main engineering problems: the design problem, the direct problem, and the choice problem. The basic equations for the study of open systems and turbomachines (continuity, energy, Euler) and the definition of the important quantities for the study of fluid machinery (head, efficiency, specific work). Statistics and similarity; use of statistics for the choice of a machine: the Cordier plot. The effect of heating and dissipation on the efficiency of the compression of gases.
Dynamic type machines: compressors, blowers, fans, and pumps, of axial and radial type: working principle, typical applications, limitations of operating conditions. (stall, cavitation, surge).
Displacement type machines: reciprocating and rotary screw/vane compressors and pumps: working principle, typical applications, limitations on the operating conditions (volumetric efficiency, maximum compression ratio, cavitation).
Similarity and characteristics curves of turbomachines and of typical fluid dynamic loadings (hydraulic circuits and choked nozzles). Determination of the operating point: matching of the characteristic curves.
The unsteady operation of turbomachines and the ways of avoiding it.
Design exercises: filling of a tank and fluid distribution circuit.
Lecture notes by the teacher, available at https://dime.aulaweb.unige.it/course/search.php?search=modulo+di+macchine
R.I. Lewis, Turbomachinery performance analysis, John Wiley and Sons
L. A. Catalano, M. Napolitano, Elementi di Macchine operatrici a fluido, Pitagora Editrice
Ricevimento: Please contact the teacher by e-mail at the address <Andrea.Cattanei@unige.it>
ANDREA CATTANEI (President)
EDWARD CANEPA
CARLO CRAVERO
FRANCESCO DEVIA
GUGLIELMO LOMONACO
LUCA ANTONIO TAGLIAFICO
VINCENZO BIANCO (President Substitute)
According to the official classes schedule, available at http://www.ingegneria.unige.it/index.php/orario-e-calendario-delle-lezioni
FLUID MACHINERY
Oral examination upon request at the end of classes, normally each Tuesday. Please contact the teacher by email <Andrea.Cattanei@unige.it> at least one week in advance.
Discussion of the subjects treated in course starting from two questions. The examination aims at evaluating physical understanding and engineering usefulness.
Pre-requisites :
Basic knowledge of Fluid mechanics, Thermodynamics and Fluid machinery.
