EXPERIMENTAL METHODS FOR FLUID MACHINERY AND ENERGY SYSTEMS
Program Overview
EXPERIMENTAL METHODS FOR FLUID MACHINERY AND ENERGY SYSTEMS
Course Overview
The module provides the basic knowledge to perform experimental measurements on fluid machinery by means of advanced measurement techniques, and it also provides the post-processing tools for the analysis of the unsteady time-signals encountered in such applications.
Aims and Content
Learning Outcomes
The aim of the course is to present and discuss the main components of a measuring chain, and to provide students with post-processing tools for statistical moments and time (frequency) dependent analysis. The basic laws governing the main fluid dynamic instrumentations are provided, and experiments are presented. The theory and development of post-processing routines will be introduced, jointly with real applications and implementations of data analysis tools in Matlab.
Aims and Learning Outcomes
The student should be able to:
- identify the proper probe for velocity and pressure fields investigation to be used, based on the specific definition of the quantities to be measured and in relation to the constraints regarding the accuracy, sensibility, spatial resolution, and frequency response;
- employ the different measuring techniques, setting the acquisition parameters for the inspection and analysis of three-dimensional unsteady flows of practical and industrial interest;
- provide a statistical analysis of an ensemble of data, as well as a detailed characterization of the dynamics of complex systems by means of advanced post-processing routines like the Fast Fourier Transform, the auto- and cross-correlation coefficients, and phase-locked ensemble averaging;
- acquire expertise in the treatment of voltage signals as well as in the development of regression and calibration curves of complex systems.
Teaching Methods
Frontal lessons will be mainly employed in the course. The basic rules describing the theory of the measurement chains, of signal analysis, and the basic operating principles of the different probes introduced into the course will be provided to the student. Experimental activities will be carried out in the Aerodynamics and Turbomachinery laboratory to provide the student with expertise in the setting and operation of the different probes presented in the course. Post-processing routines will be developed in Matlab.
Syllabus/Content
- Introduction to the main components of a measuring chain: transducers, filters, amplifiers, and A/D conversion board. Nyquist's theorem. Frequency response and dynamic calibration.
- Data statistics. Errors due to finite number of samples and samples dispersion. Mean, rms, and higher order statistical moments. Probability density function.
- Introduction to the basic laws governing different kinds of probes and possible applications.
- Pneumatic probes (1, 3, and 5 hole probes): static pressure taps, pressure transducers, and directional calibration;
- Fast response aerodynamic pressure probes (FRAPP): frequency response and dynamic calibration;
- Hot-wire anemometry (HWA): King's and Jorgensen's laws;
- Laser Doppler Velocimetry (LDV): introduction to the Doppler effect. Seeding particles and their dynamic;
- Particle Image Velocimetry (PIV): cross-correlation and magnification ratio;
- Advanced post-processing techniques: phase-locked analysis, Fourier's transform, cross-correlation, and autocorrelation functions. Applications with Matlab codes.
Recommended Reading/Bibliography
VKI lecture series, Measurement Techniques in Fluid Dynamics
Teachers and Exam Board
- Davide Lengani
- Daniele Simoni
Exam Board
- Carlo Cravero (President)
- Dario Barsi
- Davide Lengani (President Substitute)
- Daniele Simoni (President Substitute)
- Andrea Cattanei (Substitute)
- Matteo DellacasaGrande (Substitute)
- Davide Marsano (Substitute)
- Ferruccio Pittaluga (Substitute)
- Francesca Satta (Substitute)
Lessons
Lessons Start
The timetable for this course is available on the Portale EasyAcademy.
Exams
Exam Description
The examination is composed of two parts. The first consists in the discussion of an exercise focused on the post-processing of different kinds of data acquired by the research group of the professor, and provided to the student some days before the examination date. In the second part, an oral discussion of theoretical topics treated in the lessons will conclude the examination.
Assessment Methods
The oral examination will allow verifying the acquired knowledge of the student regarding the theory of the different measurement techniques, as well as the mathematical foundations of the different post-processing algorithms. With the exercise, the capability of the student in the development of a Matlab program aimed at the statistical and dynamical inspection of an ensemble of data will be verified.
Exam Schedule
- 22/12/2025, 10:00, GENOVA
- 12/01/2026, 10:00, GENOVA
- 10/02/2026, 10:00, GENOVA
- 23/03/2026, 10:00, GENOVA
- 16/06/2026, 10:00, GENOVA
- 14/07/2026, 10:00, GENOVA
- 31/07/2026, 10:00, GENOVA
- 01/09/2026, 10:00, GENOVA
- 17/09/2026, 10:00, GENOVA
Further Information
Ask the professor for other information not included in the teaching schedule.