2024-2025 / AERO0035-1

Nonlinear vibrations of aerospace structures

Duration

26h Th, 26h Pr

Number of credits

 Master MSc. in Aerospace Engineering, professional focus in aerospace engineering5 crédits 

Lecturer

Gaëtan Kerschen, Ghislain Raze

Language(s) of instruction

English language

Organisation and examination

Teaching in the first semester, review in January

Schedule

Schedule online

Units courses prerequisite and corequisite

Prerequisite or corequisite units are presented within each program

Learning unit contents

With continual interest in expanding the performance envelope of engineering systems, structural nonlinearities, which include friction, contact, nonlinear materials and large-displacement-related effects, are increasingly encountered in real-world applications. For instance, the vibration tests of two Airbus aircraft, namely the A400M and the A350XWB, revealed nonlinearities in engine mounts, hydraulic actuators, landing gears and in the auxiliary power unit. This course covers the various aspects of the vibration engineering practice from the analysis of measured data to the simulation using a finite element model. Theoretical, numerical and experimental approaches are described to learn how to recognise, model and understand nonlinear behaviour. Hands-on practice with the Nonlinear Identification to Design (NI2D) software and the study of a F-16 aircraft and of an Airbus Defence and Space satellite serve to illustrate the new methods, concepts and tools.
Course outline:
- Typical nonlinearities in real-world structures (contact, friction, large displacements, materials);
- Impact of nonlinearities on the structural vibrations;
- Nonlinear system identification from experimental data (detection, characterisation, parameter estimation);
- Nonlinear simulation using a finite element model (nonlinear modes, nonlinear frequency responses, bifurcations);
- Nonlinear designs.

Learning outcomes of the learning unit

This course contributes to the learning outcomes I.2, II.1, II.2, III.2, III.4, IV.1, VI.1, VI.2, VII.2, VII.3, VII.4, VII.5 of the MSc in aerospace engineering.

Prerequisite knowledge and skills

Advanced knowledge of the theory of linear vibrations: vibration modes, resonance frequencies, finite element analysis, time integration, single- and multiple-degree-of-freedom systems.

Planned learning activities and teaching methods

Theoretical lectures mixed with exercise sessions using the Nonlinear Identification to Design (NI2D) software.

Mode of delivery (face to face, distance learning, hybrid learning)

Face-to-face course


Additional information:

 

 

 

Course materials and recommended or required readings

Theory of Vibrations (L. Salles' course - MECA0029)

 

 

Written work / report


Further information:

Grading will be based on a project in Matlab (100% of the final grade) which will be defended in January. It is mandatory to work on this project and to deliver the requested report in due time.

 
Exam in August: oral exam only based on the course slides.
 

 

 

Work placement(s)

Organisational remarks and main changes to the course

  

 

Contacts

Gaetan Kerschen, g.kerschen@uliege.be

 
 

Association of one or more MOOCs