https://hal.archives-ouvertes.fr/hal-02486739/document

On the structural dynamics of laminated composite plates and sandwich structures; a new perspective on damping identification

Frequency maximization of laminated sandwich plates under general boundary conditions using layerwise optimization method with refined zigzag theory

Evaluation of free vibration and bending analysis of laminated composite and sandwich plates using non-polynomial Zigzag models: C 0 Finite element formulation

A mathematical model of contact interaction between two plates is presented, considering certain types of nonlinearity of each of the plates. Stress–strain state (SSS) of the interacting structural members is analyzed by the method of variational iterations, and the theorem of convergence of this method is provided. An iterative procedure for solving contact problems is developed and its convergence is also proved. Physical nonlinearity is considered by means of the method of variable parameters of elasticity. The SSS of a two-layer system of rectangular plates, depending on a type of boundary conditions as well as distances between plates, is investigated and supplemented with stress–strain curves $$\sigma _i^{(i)} (e_i^{(i)} )$$
 for each of the plates.

On the contact interaction between two rectangular plates

As an effective approach of suppressing vibrations, the constrained layer damping (CLD) has drawn wide attention from the automotive and aerospace industries. However, most of the existing investigations focus on the beam structures with CLD and few studies have been done on the plate structures with CLD. Considering the practical applications, this work studies the finite element (FE) modeling of plate structures with CLD by considering the shear and extension strains in all of three layers. To reduce the computational cost and ensure the accuracy, a simplified single-layer equivalent method is originally proposed to model the plate structure with CLD based on the equivalent material properties. In this method, the equivalent material properties are obtained by defining a new equation which includes the equivalent bending stiffness. By nonlinear regression of these responses at resonance frequencies, the equivalent bending stiffness can be obtained, and the plate structure with CLD can be regarded as a regular single-layer plate for modeling. The simulation result shows that the proposed simplified single-layer equivalent method using single-layer equivalent material properties is efficient and accurate for modeling plate structures with CLD.

Simplification of finite element modeling for plates structures with constrained layer damping by using single-layer equivalent material properties

A multilayer anisotropic plate model with warping functions for the study of vibrations reformulated from Woodcock's work

Complex power distribution analysis in plates covered with passive constrained layer damping patches

Two multilayered plate models with transverse shear warping functions issued from three dimensional elasticity equations


 Aerospace industry OEMs and suppliers are progressing their engineering processes and performance to the next maturity level gearing to digital thread solutions. Current challenges like continuous engineering, virtual certification, distributed development, consolidated virtual proving grounds, homologation, digital twin and operational applications, require well informed decision making in a comprehensive, reliable, traceable and customizable environment. In particular, in aerospace domain, with widespread tight collaborative ecosystems between integrators and suppliers, the capability of tracing each decision and its underlying artifacts becomes a key value of an engineering platform. This paper will outline a middleware approach to reuse generated artifacts and their relationships in a federated engineering environment supporting a "best tool for the job" approach by introducing a layer providing unification and consistency throughout all managed artifacts. Based on an exemplary eVTOL setup, the benefits of integrated data and workflows from specification to virtual design verification are highlighted to motivate their value towards realisation of MBSE methodologies.


Towards Certification by Simulation with Model-based continuous Engineering Processes showcased on eVTOL Application

Acoustic requirements for space habitats are stringent and involve a combination of noise sources minimization and public address and general alarm (PAGA) system validation. Simulation solutions are essential for demonstrating compliance requirement as early as possible and continuously
 throughout the development cycle of the spacecraft. Space habitats' sound field can be computationally challenging to predict in a deterministic manner for most of the audible spectrum as the volume can be important. For this application, an initial PAGA system design assessment was performed
 using Ray-Tracing, a geometric statistical method, which must be validated using a deterministic method. For validation purpose, the Boundary Element Method (BEM) was chosen for this application. Given the size of the structure and the desired frequency range, the BEM model was very large,
 containing over 250,000 wetted nodes, and a standard BEM solver required approximately 200GB of RAM. To limit computing hardware constraints, a newly implemented commercially available H-Matrix BEM solver was used. Pressure maps of a PAGA system simulation on a generic space habitat resulting
 from the Ray-Tracing and H-Matrix BEM solvers are compared to a standard BEM simulation. Results are compared both in terms of accuracy and computational performance, showing the advantages of using multiple simulation methods at various stages of the design.

Alexis Castel

Papers

A multilayer anisotropic plate model with warping functions for the study of vibrations reformulated from Woodcock's work

Complex power distribution analysis in plates covered with passive constrained layer damping patches

Two multilayered plate models with transverse shear warping functions issued from three dimensional elasticity equations

Towards Certification by Simulation with Model-based continuous Engineering Processes showcased on eVTOL Application

H-Matrix BEM application and validation for space habitat