Structural dynamics

Objectives
The aim of this course is to acquire the concepts and methods required to study the dynamics of continuous structures.
Skills acquired

Be able to equate a system of N identical mechanical oscillators
Be able to implement PFD for a continuous system
Be able to use the notion of FRF in a system with N ddl
Be able to make the link between N ddl and continuous systems
Be able to numerically model the dynamics of a structure using finite elements: choice of elements, choice of boundary conditions, modal analysis, response in forced regime
Be able to make the link between the type of excitation and the response of the structure (excitation-mode matching in terms of frequency and spatial distribution of excitation).


Skills acquired at independent mastery level

Mobilize a wide range of fundamental and technical sciences related to aeronautical and space mechanical systems, and the associated capacity for analysis and synthesis
Design and dimension mechanical systems
Choose and implement the relevant analysis and characterization methods for mechanical systems
Communicate and work as part of a team Manage and lead a work unit or project group
Integrate into a professional environment in France or abroad Communicate both orally and in writing in English


Skills acquired at the supervised master's level

Design, dimension, implement and test a metallic or composite repair/modification
Have a global systemic approach to mechanical systems Reason in a context of international regulatory constraints
Anticipate, decide in a situation of uncertainty Be results-oriented (costs, deadlines, quality) and customer-oriented
Evaluate one's own skills and steer one's career path


Skills acquired - Level : In progress

Integrate financial, legal and contractual aspects into engineering practice

AP8SADDS
Dynamics of mechanical oscillators at 1 and 2 ddl: equation and analytical solution in free and forced regimes, spectral analysis with FRF
Static continuum mechanics
Fourier transform / Laplace / Basics of linear algebra : AP5SIMAI

Contents

Introduction to the dynamics of continuous media: propagation, dynamics of structures
PFD in continuous media
Case study of a continuous structure - the beam in compression - approach by N mass-springs, and analytical approach
Case study of a continuous structure - the beam in bending - analytical and numerical approach
Modal analysis : from 1 problem with N ddl to N problems with 1 ddl
Response to forced excitation by modal synthesis
TP1: Experimental observations of Chladni figures and their simulation on FEM software. Experimental-simulation comparison. Modal analysis of an aircraft-like structure.
TP2: FEM simulation of the dynamic behavior of an aircraft or helicopter component to make the link with fatigue behavior and identify damage risks

Pedagogical acquisition method

Teaching associated with online resources under Moodle
Integrated lecture/DD approach with in-class demonstrations
Strong connection between TDs and TPs

Aeronautical structures