Time filter

Source Type

Saint-Ouen-l'Aumône, France

Dauchez N.,CNRS Roberval Laboratory (Mechanical Research Unit) | Hayot M.,Supmeca | Denis S.,CEA DAM Ile-de-France
Journal of the Acoustical Society of America | Year: 2016

This paper deals with nonporous windscreens used for reducing noise in infrasonic measurements. A model of sound transmission using a modal approach is derived. The system is a square plate coupled with a cavity. The model agrees with finite element simulations and measurements performed on two windscreens: a cubic windscreen using a material recommended by Shams, Zuckerwar, and Sealey [J. Acoust. Soc. Am. 118, 1335-1340 (2005)] and an optimized flat windscreen made out of aluminum. Only the latter was found to couple acoustical waves below 10 Hz without any attenuation. Moreover, wind noise reduction measurements show that nonporous windscreens perform similarly as a pipe array by averaging the pressure fluctuations. These results question the assumptions of Shams et al. and Zuckerwar [J. Acoust. Soc. Am. 127, 3327-3334 (2010)] about compact nonporous windscreens design and effectiveness. © 2016 Acoustical Society of America.

Ducellier G.,University of Technology of Troyes | Yvars P.-A.,Supmeca | Eynard B.,Compiegne University of Technology
International Journal on Interactive Design and Manufacturing | Year: 2014

This paper focuses on the impact of Design Change Orders (DCO) on the product data into a PLM platform. In a context of concurrent engineering, we concentrate on the management of product data associated to the product structure. As PLM platform architecture is not fully adapted to conduct DCO on the product data, we propose a specific approach for facilitating DCO execution and comprehension. In this context, a constraint based approach is proposed. The aim of this approach is to provide a view of all the product data concerned by the DCO at the beginning of the DCO process. Based on this view, called product data constraint graph, the project leader can assign the corresponding resources to the DCO process. An example illustrates the benefits of our proposition and the first results concerning this underdevelopment approach are presented. © 2014 Springer-Verlag France.

Yannou B.,Ecole Centrale Paris | Yvars P.-A.,Supmeca | Hoyle C.,Oregon State University | Chen W.,Northwestern University
Journal of Engineering Design | Year: 2013

While the marketing literature has advocated for decades that new products should be designed for intended and anticipated consumer usages, the engineering literature mostly proposes optimisation of product performances independent of specific users' skills, anticipated usage scenarios, and competing products in the market. In contrast to tedious market studies which assume an existing market experience for products and optimisation approaches based upon static product performances, we propose an adaptable approach to designing a product or product family: the set-based design by usage coverage simulation. It starts with generating a usage scenario space for a set of representative users. Next, considering a candidate set of products, one proceeds to the constraint satisfaction problem computations of feasible usage scenarios, assuming that physics-based models of performances are available. The comparison between the expected and feasible usage scenarios at the scale of a single user leads to Usage Coverage Indicators and finally to a preferred product which best covers the usage scenario space. At the level of a targeted consumer group, the approach provides a market share simulation for competing products or members of a scale-based product family. The design of a family of jigsaws thoroughly illustrates our approach. © 2013 Copyright Taylor and Francis Group, LLC.

Krommer M.,Johannes Kepler University | Berik P.,Johannes Kepler University | Benjeddou A.,Supmeca
Acta Mechanica | Year: 2013

This paper is concerned with the analysis of two types of piezoelectric torsion transducers using the d 15-effect of mono-morph piezoelectric materials. The first problem is concerned with a bi-morph transducer made of two identical mono-morph straight rods, which are perfectly bonded to each other along their width; the polarization direction is parallel, but opposite in sign, such that the piezoelectric material parameter d 15 has an opposite sign as well. The second problem sandwiches the bi-morph transducer between two identical elastic face layers. In both cases, the resulting transducer represents a torsion transducer. Therefore, we analyze the electromechanically coupled problem in the framework of Saint Venant's torsion theory for straight rods taking into account the electrical problem as well. The results of our approach are compared to electromechanically coupled three-dimensional finite element computation and a very good agreement for the mechanical as well as the electrical entities is achieved, in particular for the rate-of-twist, the axial warping function, and the sensed voltage. © 2013 Springer-Verlag Wien.

Tchertchian N.,Avenue Of Luniversite | Millet D.,Avenue Of Luniversite | Yvars P.-A.,Supmeca
Procedia CIRP | Year: 2014

This article aims to present an approach based on a combination of life cycle analysis methods (LCA) and problem solving by constraint satisfaction (CSP). This original approach makes it possible to vary the design of the different dimensions of the functional units of a complex system and thus to make it easier to identify the best architecture along with the best functional definition of the system. Our approach (EcoCSP) presented allows to negotiate performance to move towards an environmental optimum corresponding to a set of acceptable specifications. The EcoCSP approach is implemented to define the functional performance of a green passengers' ferry. © 2014 Published by Elsevier B.V.

Discover hidden collaborations