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Nantes, France

Andriyana A.,University of Malaya | Ch'ng S.Y.,University of Selangor | Brulliard V.,CNRS Research Institute in Civil Engineering and Mechanics | Verron E.,CNRS Research Institute in Civil Engineering and Mechanics | Le Corre S.,Polytechnic Nantes
Constitutive Models for Rubber IX - Proceedings of the 9th European Conference on Constitutive Models for Rubbers, ECCMR

Elastomer is a unique material capable to absorb fluid molecule when in contact with liquid. In this case, the incorporation of filler such as carbon black into elastomers is known to increase their network stiffness and hence restrict the resulting amount of equilibrium swelling exhibited by the elastomers. However, when the elastomers are simultaneously subjected to complex mechanical loading, the role of filler in the corresponding coupled mechanical deformation-liquid diffusion in elastomers is not well established. The present contribution focuses on the development of a continuum model to predict the equilibrium swelling of carbon black filled elastomers in solvents in the presence of static mechanical deformation. To this end, the fluid-solid mixture is viewed as a single, homogenized continuum body. The proposed model is implemented into commercial finite element analysis software ABAQUS to simulate the equilibrium swelling of elastomers in the absence (stress-free swelling) and in the presence (constrained swelling) of mechanical loading. It is shown that the model gives a qualitatively good agreement with experimental observations. © 2015 Taylor and Francis Group. Source

Rasilo P.,Aalto University | Rasilo P.,Ghent University | Lemesle M.-A.,Polytechnic Nantes | Belahcen A.,Aalto University | And 2 more authors.
IEEE Transactions on Energy Conversion

An interior permanent-magnet (PM) motor is modeled by a combined analytical-numerical approach, in which the relationships between the stator currents and flux linkages are identified with static finite-element (FE) analysis. In addition to the previous approaches using the current space vector as the state variable, new models are also developed using the flux-linkage space vector, which leads to more convenient time-integration of the voltage equations. In order to account for the zero-sequence effects in delta connection, the models also include either the zero-sequence flux or current as an additional state variable. Finally, the possibilities of deriving the required quantities as partial derivatives of the magnetic field energy are discussed. The energy-based approaches avoid inaccuracies related to torque computation and thus allow better satisfying the power balance in the state-space model. We show the ability of the developed state-space models to predict the currents and torque equally to a nonlinear time-stepping FE model with much less computational burden. The results are validated by means of measurements for a prototype machine in both star and delta connections. In addition, we also demonstrate the effect of the zero-sequence current on the torque ripple in case of a delta-connected stator winding. © 1986-2012 IEEE. Source

Paseta L.,University of Zaragoza | Potier G.,Polytechnic Nantes | Sorribas S.,University of Zaragoza | Sorribas S.,University of Manchester | Coronas J.,University of Zaragoza
ACS Sustainable Chemistry and Engineering

Besides the substitution or minimization of the use of harmful solvents, one essential goal of chemistry is to try to avoid their use altogether whenever possible. In the case of the synthesis of MOFs (metal-organic frameworks), this can only be achieved by finding alternatives to conventional processes. An example is the approach described here which involves working at high pressure (at 0.31 GPa) without using a solvent. This has evident advantages over mechanochemical synthesis by grinding or milling (also a solventless process) where the sample is submitted to attrition. The present paper reports the simple high pressure synthesis of the ZIF (zeolitic imizadolate framework) ZIF-8. This methodology enables fast synthesis of MOF materials and offers new insights into their industrial implementation. In addition, this technique could be applied to the synthesis of other MOFs and even COFs (covalent organic frameworks). © 2016 American Chemical Society. Source

Puchnin M.,Czech Technical University | Anisimov E.,Czech Technical University | Cejp J.,Czech Technical University | Kunka I.,Czech Technical University | Vicens S.,Polytechnic Nantes
Manufacturing Technology

The investigation of mechanical properties of aluminum alloys by using express-methods is discussed in the present paper. Such properties are hardness, elastic modulus E and yield strength Rp0.2. Tensile test with extensometer and automated ball indentation test (ABI) with 5 mm ball indenter performed in order to obtain the correlations for the basic mechanical properties of aluminum alloys. The results of newly developed method of revealing the microstructure, which involves plastic deformation, show its potential of applicability in engineering practice when measuring the microstructural and submicrostructural features. © 2014. Published by Manufacturing Technology. Source

Paseta L.,University of Zaragoza | Potier G.,Polytechnic Nantes | Abbott S.,Abbott Laboratories | Abbott S.,University of Leeds | Coronas J.,University of Zaragoza
Organic and Biomolecular Chemistry

Hansen solubility parameters (HSP) have found their greatest use in the evaluation of solvent-polymer chemical interactions. Given their great interest among the scientific community, host-guest interactions in metal-organic frameworks (MOFs), with organic and inorganic moieties, could benefit from a HSP approach. In this work we have initiated the application of HSP to the study of caffeine encapsulation in MOFs ZIF-8 and NH2-MIL-88B(Fe). However, the availability of HSP for MOFs is nearly zero. As a first step to evaluating the potential of HSP for rational design we have made the simplifying assumption that the HSP distance of the caffeine-ligand interaction (i.e. ignoring the metal and the MOF structure) dominates the ability to form a MOF host-guest system. Although much work remains to be done, the first indications are that this approach has much potential. © The Royal Society of Chemistry 2015. Source

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