Manufacturing requirements in design: The RTM process in aeronautics

A sub-unit of an aeronautical structure (fuselage, fin, wing, etc.) consists of a set of components fixed rigidly together. One of today’s major industrial challenges is to produce these sub-units out of composite materials in order to increase the level of integration and reduce and cost. This article describes a procedure to assist in the industrialisation of aeronautical components produced from composite materials in a design for manufacturing context. In a multi-expertise approach, the problem of optimising integration is combined with the feasibility of injection for the Resin Transfer Molding process. This approach then takes into account admissible manufacturing deviations, defined from a classification of the structure parts. The limits set for admissible deviations guarantee the mechanical behaviour of the assembled component and the requirements of the assembly as a whole. Finally, an industrialisation solutions space is defined. A constraint satisfaction problem solver is used to carry out this research with a spar from a horizontal plane in an aircraft used to illustrate the procedure

Visualization of and Access to CloudSat Vertical Data through Google Earth

Online tools, pioneered by the Google Earth (GE), are facilitating the way in which scientists and general public interact with geospatial data in real three dimensions. However, even in Google Earth, there is no method for depicting vertical geospatial data derived from remote sensing satellites as an orbit curtain seen from above. Here, an effective solution is proposed to automatically render the vertical atmospheric data on Google Earth. The data are first processed through the Giovanni system, then, processed to be 15-second vertical data images. A generalized COLLADA model is devised based on the 15-second vertical data profile. Using the designed COLLADA models and satellite orbit coordinates, a satellite orbit model is designed and implemented in KML format to render the vertical atmospheric data in spatial and temporal ranges vividly. The whole orbit model consists of repeated model slices. The model slices, each representing 15 seconds of vertical data, are placed on the CloudSat orbit based on the size, scale, and angle with the longitude line that are precisely and separately calculated on the fly for each slice according to the CloudSat orbit coordinates. The resulting vertical scientific data can be viewed transparently or opaquely on Google Earth. Not only is the research bridged the science and data with scientists and the general public in the most popular way, but simultaneous visualization and efficient exploration of the relationships among quantitative geospatial data, e.g. comparing the vertical data profiles with MODIS and AIRS precipitation data, becomes possible

Des Cantons-de-l’Est à l’Estrie

Les auteurs reprennent, dans l'oeuvre de Blanchard, les chapitres sur les Cantons-de-l'Est et en font la mise à jour. La physiographie de même que l'évolution glaciaire et post-glaciaire du milieu physique sont dorénavant mieux connues. L'agriculture se caractérise par l'élevage et la production laitière, le bois demeurant une activité d'appoint. Le développement récent a été influencé par les transports routiers, successeurs du transport ferroviaire. La structure industrielle repose toujours sur les secteurs traditionnels que sont le bois, l'amiante et le textile auxquels se sont ajoutées récemment les industries de micro-technologies. Le tourisme est dorénavant considéré comme l'industrie la plus prometteuse. L'Estrie est-elle encore cette sublime région du Québec que dépeint le dithyrambe de Blanchard ?The authors review and bring up to date the information pertaining to the Eastern Townships in Blanchard's work. With present day knowledge, the physical milieu is more fully understood, particularly the glacial and post-glacial periods. Cattle, pig and milk production are the mainstays of the agriculture industry, while wood cutting is on the decline. Road transportation has supplanted railroads as a main factor in the area's recent development. The main industrial sector is still identified to wood transformation, asbestos mining and textile production; these old industries are being gradually replaced by smaller ones dealing with micro-technologies. Tourism is now an important sector of economic activity. Are the Eastern Townships still that idyllic area of Québec that Blanchard presented in his work

Indicateurs de durabilité pour la conception préliminaire de bureaux du point de vue énergétique

The building sector currently represents 40% of the energy consumption and one of the major emitters of greenhouse gases in the world. This, combined with the characteristic long lifespan of buildings, means that the decisions behind building design have long-term and multidimensional impacts on both society and the environment. As a result, there is a growing interest in the assessment of buildings based on the concept of sustainability, considering its three basic dimensions: economic, ecological and social. However, current evaluation systems are usually developed in the context of the declaration or certification of buildings, while only a limited number are designed to provide decision-support during the preliminary design phase. It is during these early design stages that key decisions such as construction principles and operation strategies are defined, usually with a limited amount of information available. In order to assist in decision-making during the preliminary building design, a set of indicators is proposed in this present work to evaluate early design alternatives by following a life-cycle analysis approach and according to the three pillars of sustainability. Indicator selection is based on consensus from the international projects and initiatives that compose the state of the art, as well as operational aspects such as database availability for calculation parameters, the evolution of information available and of specific design decisions at every stage of the design process. The conclusions of this study are focused on the energy design of commercial buildings, specifically offices, in the French context

The incidence and types of physical contact associated with body checking regulation experience in 13–14 year old Ice Hockey players

Background: Ice hockey has one of the highest sport participation and injury rates in youth in Canada. Body checking (BC) is the predominant mechanism of injury in leagues in which it is permitted. The objectives of this study were to determine whether the incidence and types of physical contact differ for Bantam players (aged 13–14 years) who were exposed to BC at Pee Wee level (aged 11–12 years) in Calgary, Alberta versus Bantam players who were not exposed to BC at Pee Wee level in Québec City, Québec. All teams were exposed to BC at bantam level; Methods: A cohort study was conducted in Québec City and Calgary. Sixteen games for Calgary and 15 for Québec City were randomly selected and analysed with a validated observation system to quantify five intensities of physical contact and to observe different types of physical contact such as slashing and holding; Results: A total of 5610 incidences of physical contact with the trunk and 3429 other types of physical contact were observed. Very light intensity trunk contact was more frequent in Calgary (adjusted incidence RR (ARR): 1.71; 95% CI: 1.28–2.29). Holding (ARR: 1.04; 95% CI: 1.02–1.07) and slashing (ARR: 1.38; 95% CI: 1.07–1.77) were more frequent in Calgary; Conclusion: Results suggest that players’ physical contacts differ between Bantam leagues in which BC was permitted at Pee Wee level and leagues in which it was not permitted until Bantam level. View Full-Tex

Analyse expérimentale et modélisation d’un échangeur-stockeur contenant des matériaux à changement de phase

Un outil de simulation dynamique a été développé afin d’étudier le comportement thermique d’un échangeur-stockeur contenant des matériaux à changement de phase dédié au rafraîchissement de l’air dans le bâtiment. Ce modèle prend en compte le phénomène de fonte par contact induit par la variation de densité entre les phases solide et liquide du MCP. Les résultats expérimentaux sont présentés et analysés afin de dégager le comportement dynamique de l’échangeur-stockeur soumis à un écoulement d’air à vitesse constante et à température d’entrée constant

Analyse des tolérances géométriques dans un contexte multi-expertises, application à une turbine de moteur d'hélicoptère

L'amélioration de la performance d'un turbomoteur d'hélicoptère implique l'optimisation du rendement énergétique des différents composants constitutifs, et plus particulièrement la maîtrise des jeux entre les sommets des aubes de la turbine haute pression et le stator. Les outils de chaînes de cotes prennent en compte la dispersion de fabrication des pièces et les défauts d'assemblage. Cela permet d'assurer l'interchangeabilité des différents composants et de garantir qu'une turbine assure différentes fonctions de service, la turbine étant modélisée en solides infiniment rigides. Mais, cette approche ne prend pas en compte des effets thermomécaniques. Pourtant, les différents régimes de fonctionnement d'un moteur d'hélicoptère rendent indispensables l'intégration des effets induits par le cycle thermodynamique. L'objet de cet article est de montrer comment la mise en œuvre d'outils de chaînes de cotes et d'outils thermomécaniques peut contribuer à maîtriser les jeux en sommet d'aube d'une turbine haute pression

Experimental Study of an Air-PCM Heat Exchanger: Melting in a Cylindrical Container

This paper presents experimental results of an air-PCM heat exchanger, with an in-line arrangement of cylindrical containers. The objective is to highlight the physical phenomena occurring in a single container during the phase change. Temperature and airflow measures were carried out. These values were used to find the heat exchanges on the container. The experimental heat values were compared and validated with the theoretical heat stored obtained from the material properties. An only conduction 1D radial model is proposed to describe the melting front in the container.Keywords: phase change materials, thermal storage unit, cylinder, latent heat, radial conduction