IMT Institutional Repository: No conditions. Results ordered -Date Deposited. 2022-08-12T18:41:16ZEPrintshttp://eprints.imtlucca.it/images/logowhite.pnghttp://eprints.imtlucca.it/2017-03-21T12:12:26Z2017-03-21T12:12:26Zhttp://eprints.imtlucca.it/id/eprint/3672This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/36722017-03-21T12:12:26ZOverall thermomechanical properties of layered materials for energy devices applicationsThis paper is concerned with the analysis of effective thermomechanical properties of multi-layered materials of interest for solid oxide fuel cells (SOFC) and lithium ions batteries fabrication. The recently developed asymptotic homogenization procedure is applied in order to express the overall thermoelastic constants of the first order equivalent continuum in terms of microfluctuations functions, and these functions are obtained by the solution of the corresponding recursive cell problems. The effects of thermal stresses on periodic multi-layered thermoelastic composite reproducing the characteristics of solid oxide fuel cells (SOFC-like) are studied assuming periodic body forces and heat sources, and the solution derived by means of the asymptotic homogenization approach is compared with the results obtained by finite elements analysis of the associate heterogeneous material.Andrea Bacigalupoandrea.bacigalupo@imtlucca.itLorenzo MoriniAmdrea Piccolroaz2016-03-15T10:30:26Z2016-03-15T10:30:26Zhttp://eprints.imtlucca.it/id/eprint/3238This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32382016-03-15T10:30:26ZInterfacial cracks in bi-materials solids: Stroh
formalism and skew-symmetric weight functionsLorenzo Morinilorenzo.morini@imtlucca.itEnrico RadiAlexander MovchanNatalia Movchan2016-03-15T10:15:54Z2016-03-15T10:15:54Zhttp://eprints.imtlucca.it/id/eprint/3237This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32372016-03-15T10:15:54ZLoading profile effects on dynamic crack
propagation in couple stress elastic materialsAmdrea PiccolroazLorenzo Morinilorenzo.morini@imtlucca.itGennady MishurisP.A. Gourgiotis2016-03-15T10:05:20Z2016-03-15T10:05:20Zhttp://eprints.imtlucca.it/id/eprint/3236This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32362016-03-15T10:05:20ZDynamic energy release rate in couple-stress elasticityThis paper is concerned with energy release rate for dynamic steady state crack problems in elastic materials with microstructures. A Mode III semi-infinite crack subject to loading applied on the crack surfaces is considered. The micropolar behaviour of the material is described by the theory of couple-stress elasticity developed by Koiter. A general expression for the dynamic J-integral including both traslational and micro-rotational inertial contributions is derived, and the conservation of this integral on a path surrounding the crack tip is demonstrated.Lorenzo Morinilorenzo.morini@imtlucca.itAmdrea PiccolroazGennady Mishuris2016-03-15T10:00:03Z2016-03-15T10:08:29Zhttp://eprints.imtlucca.it/id/eprint/3235This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32352016-03-15T10:00:03ZAnalysis of interfacial crack propagation under asymmetric loading in anisotropic materialsThis paper considers a steady-state crack propagating along an interface between dissimilar orthotropic materials under an asymmetric load. Although most of the known results so far deal with symmetric loading, it has been shown recently that a significant asymmetry in the applied loading may lead to a pronounced effect in terms of the values of the SIFs. The aim of the paper is to extend these results from the static case to a moving crack. In particular, we show the significance of the asymmetry of the loading for computing the energy release rate.Lewis PryceLorenzo Morinilorenzo.morini@imtlucca.itGennady Mishuris2016-03-15T09:31:37Z2016-03-15T09:31:37Zhttp://eprints.imtlucca.it/id/eprint/3234This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32342016-03-15T09:31:37ZInterfacial Cracks in Piezoelectric Bimaterials: an approach based on Weight Functions and Boundary Integral EquationsThe focus of this paper is on the analysis of a semi-infinite crack lying along a perfect interface in a piezoelectric bimaterial with arbitrary loading on the crack faces. Making use of the extended Stroh formalism for piezoelectric materials combined with Riemann-Hilbert formulation, general expressions are obtained for both symmetric and skew-symmetric weight functions associate with plane crack problems at the interface between dissimilar anisotropic piezoelectric media. The effect of the coupled electrical fields is incorporated in the derived original expressions for the weight function matrices. These matrices are used together with Betti's reciprocity identity in order to obtain singular integral equations relating the extended displacement and traction fields to the loading acting on the crack faces. In order to study the variation of the piezoelectric effect, two different poling directions are considered. Examples are shown for both poling directions with a number of mechanical and electrical loadings applied to the crack faces.Lewis PryceLorenzo Morinilorenzo.morini@imtlucca.itD. AndreevaA. Zagnetko2016-03-15T09:17:00Z2016-03-15T09:17:00Zhttp://eprints.imtlucca.it/id/eprint/3233This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32332016-03-15T09:17:00ZAnalysis of the validity of the asymptotic techniques in the lower hybrid wave equation solution for reactor applicationsKnowing that the lower hybrid (LH) wave propagation in tokamak plasmas can be correctly described with a full wave approach only, based on fully numerical techniques or on semianalytical approaches, in this paper, the LH wave equation is asymptotically solved via the Wentzel-Kramers-Brillouin (WKB) method for the first two orders of the expansion parameter, obtaining governing equations for the phase at the lowest and for the amplitude at the next order. The nonlinear partial differential equation(PDE) for the phase is solved in a pseudotoroidal geometry (circular and concentric magnetic surfaces) by the method of characteristics. The associated system of ordinary differential equations for the position and the wavenumber is obtained and analytically solved by choosing an appropriate expansion parameter. The quasilinear PDE for the WKB amplitude is also solved analytically, allowing us to reconstruct the wave electric field inside the plasma. The solution is also obtained numerically and compared with the analytical solution. A discussion of the validity limits of the WKB method is also given on the basis of the obtained results.A. CardinaliLorenzo Morinilorenzo.morini@imtlucca.itC. CastaldoR. CesarioF. Zonca2016-03-15T08:52:08Z2016-03-18T11:01:35Zhttp://eprints.imtlucca.it/id/eprint/3232This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32322016-03-15T08:52:08ZContribution of Tore Supra in preparation of ITERTore Supra routinely addresses the physics and technology of very long-duration plasma discharges, thus bringing precious information on critical issues of long pulse operation of ITER. A new ITER relevant lower hybrid current drive (LHCD) launcher has allowed coupling to the plasma a power level of 2.7 MW for 78 s, corresponding to a power density close to the design value foreseen for an ITER LHCD system. In accordance with the expectations, long distance (10 cm) power coupling has been obtained. Successive stationary states of the plasma current profile have been controlled in real-time featuring (i) control of sawteeth with varying plasma parameters, (ii) obtaining and sustaining a 'hot core' plasma regime, (iii) recovery from a voluntarily triggered deleterious magnetohydrodynamic regime. The scrape-off layer (SOL) parameters and power deposition have been documented during L-mode ramp-up phase, a crucial point for ITER before the X-point formation. Disruption mitigation studies have been conducted with massive gas injection, evidencing the difference between He and Ar and the possible role of the q = 2 surface in limiting the gas penetration. ICRF assisted wall conditioning in the presence of magnetic field has been investigated, culminating in the demonstration that this conditioning scheme allows one to recover normal operation after disruptions. The effect of the magnetic field ripple on the intrinsic plasma rotation has been studied, showing the competition between turbulent transport processes and ripple toroidal friction. During dedicated dimensionless experiments, the effect of varying the collisionality on turbulence wavenumber spectra has been documented, giving new insight into the turbulence mechanism. Turbulence measurements have also allowed quantitatively comparing experimental results with predictions by 5D gyrokinetic codes: numerical results simultaneously match the magnitude of effective heat diffusivity, rms values of density fluctuations and wavenumber spectra. A clear correlation between electron temperature gradient and impurity transport in the very core of the plasma has been observed, strongly suggesting the existence of a threshold above which transport is dominated by turbulent electron modes. Dynamics of edge turbulent fluctuations has been studied by correlating data from fast imaging cameras and Langmuir probes, yielding a coherent picture of transport processes involved in the SOL. Corrections were made to this article on 6 January 2012. Some of the letters in the text were missing.B. SaouticJ. AbiteboulL. AllegrettiS. AllfreyJ.M. AnéT. AnielA. ArgouarchJ.F. ArtaudM.H. AumenierS. BalmeV. BasiukO. BaulaigueP. BayettiA. BécouletM. BécouletM.S. BenkaddaF. BenoitG. Berger-byJ.M. BernardB. BertrandP. BeyerA. BigandJ. BlumD. BoilsonG. BonhommeH. Bottollier-CurtetC. BouchandF. BouqueyC. BourdelleS. BourmaudC. BraultS. BrémondC. BrossetJ. BucalossiY. BuravandP. CaraV. Catherine-DumontA. CasatiM. ChantantM. ChatelierG. ChevetD. CiazynskiG. CiraoloF. ClairetM. Coatanea-GouachetL. ColasL. ComminE. CorbelY. CorreX. CourtoisR. DachicourtM. Dapena FebrerM. Davi JoannyR. DaviotH. De EschJoan DeckerP. DecoolP. DelaporteE. DelchambreE. DelmasL. DelpechC. DesgrangesP. DevynckT. DittmarL. DoceulD. DouaiH. DougnacJ.L. DuchateauB. DuguéN. DumasR. DumontA. DurocherF.X. DuthoitA. EkedahlD. ElbezeM. El KhaldiF. EscourbiacF. FaisseG. FalchettoM. FargeJ.L. FarjonM. FauryN. FedorczakC. Fenzi-BonizecM. FirdaoussY. FrauelX. GarbetJ. GarciaJ.L. GardareinL. GargiuloP. GaribaldiE. GauthierO. GayeA. GéraudM. GeynetP. GhendrihI. GiacaloneS. GibertC. GilG. GiruzziM. GonicheV. GrandgirardC. GrisoliaG. GrosA. GrosmanR. GuigonD. GuilhemB. GuillerminetR. GuirletJ. GunnO. GurcanS. HacquinJ.C. HatchressianP. HennequinC. HernandezP. HertoutS. HeurauxJ. HillairetG.T. HoangC. HonoreM. HouryT. HutterP. HuynhG. HuysmansF. ImbeauxE. JoffrinJ. JohnerL. Jourd'HeuilY.S. KatharriaD. KellerS.H. KimM. KocanM. KubicB. LacroixV. LamaisonG. LatuY. LausenazC. LavironF. LerouxL. LetellierM. LipaX. LitaudonT. LoarerP. LotteS. MadeleineP. MagaudP. MagetR. MagneL. ManencY. MarandetG. MarbachJ.L. MaréchalL. MarfisiC. MartinG. MartinV. MartinA. MartinezJ.P. MartinsR. MassetD. MazonN. MelletL. MercadierA. MerleD. MeshcheriakovO. MeyerL. MillionM. MissirlianP. MollardV. MoncadaP. Monier-GarbetD. MoreauP. MoreauLorenzo Morinilorenzo.morini@imtlucca.itM. NanniniM. Naiim HabibE. NardonH. NehmeC. NguyenS. NicolletR. NouilletasT. OhsakoM. OttavianiS. PamelaH. ParratP. PastorA.L. PecquetB. PégouriéY. PeyssonI. PorchyC. PortafaixM. PreynasM. ProuJ.M. RaharijaonaN. RavenelC. ReuxP. ReynaudM. RichouH. RocheP. RoubinR. SabotF. Saint-LaurentS. SalascaF. SamailleA. SantagiustinaY. SarazinA. SemerokJ. SchlosserM. SchneiderM. SchubertF. SchwanderJ.L. SéguiG. SeligP. SharmaJ. SignoretA. SimoninS. SongE. SonnendrukerF. SourbierP. SpuigP. TamainM. TenaJ.M. TheisD. ThouveninA. TorreJ.M. TravèreE. TsitroneJ.C. ValletE. Van Der PlasA. VatryJ.M. VergerL. VermareF. VillecrozeD. VillegasR. VolpeK. VulliezJ. WagrezT. WautersL. ZaniD. ZarzosoX.L. Zou2016-03-15T08:47:07Z2016-03-15T08:47:07Zhttp://eprints.imtlucca.it/id/eprint/3231This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32312016-03-15T08:47:07ZRF current drive and plasma fluctuationsThe role played by electron density fluctuations near the plasma edge on rf current drive in tokamaks is assessed quantitatively. For this purpose, a general framework for incorporating density fluctuations in existing modelling tools has been developed. It is valid when rf power absorption takes place far from the fluctuating region of the plasma. The ray-tracing formalism is modified in order to take into account time-dependent perturbations of the density, while the Fokker–Planck solver remains unchanged. The evolution of the electron distribution function in time and space under the competing effects of collisions and quasilinear diffusion by rf waves is determined consistently with the time scale of fluctuations described as a statistical process. Using the ray-tracing code C3PO and the 3D linearized relativistic bounce-averaged Fokker–Planck solver LUKE, the effect of electron density fluctuations on the current driven by the lower hybrid (LH) and the electron cyclotron (EC) waves is estimated quantitatively. A thin fluctuating layer characterized by electron drift wave turbulence at the plasma edge is considered. The effect of fluctuations on the LH wave propagation is equivalent to a random scattering process with a broadening of the poloidal mode spectrum proportional to the level of the perturbation. However, in the multipass regime, the LH current density profile remains sensitive to the ray chaotic behaviour, which is not averaged by fluctuations. The effect of large amplitude fluctuations on the EC driven current is found to be similar to an anomalous radial transport of the fast electrons. The resulting lower current drive efficiency and broader current profile are inYves PeyssonJoan DeckerLorenzo Morinilorenzo.morini@imtlucca.itS. Coda2016-03-15T08:44:33Z2016-03-18T10:58:52Zhttp://eprints.imtlucca.it/id/eprint/3230This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32302016-03-15T08:44:33ZA versatile ray-tracing code for studying rf wave propagation in toroidal magnetized plasmasA new ray-tracing code named C 3 PO has been developed to study the propagation of arbitrary electromagnetic radio-frequency (rf) waves in magnetized toroidal plasmas. Its structure is designed for maximum flexibility regarding the choice of coordinate system and dielectric model. The versatility of this code makes it particularly suitable for integrated modeling systems. Using a coordinate system that reflects the nested structure of magnetic flux surfaces in tokamaks, fast and accurate calculations inside the plasma separatrix can be performed using analytical derivatives of a spline-Fourier interpolation of the axisymmetric toroidal MHD equilibrium. Applications to reverse field pinch magnetic configuration are also included. The effects of 3D perturbations of the axisymmetric toroidal MHD equilibrium, due to the discreteness of the magnetic coil system or plasma fluctuations in an original quasi-optical approach, are also studied. Using a Runge–Kutta–Fehlberg method for solving the set of ordinary differential equations, the ray-tracing code is extensively benchmarked against analytical models and other codes for lower hybrid and electron cyclotron waves.Y. PeyssonJoan DeckerLorenzo Morinilorenzo.morini@imtlucca.it2016-03-14T14:23:16Z2016-03-14T14:23:16Zhttp://eprints.imtlucca.it/id/eprint/3229This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32292016-03-14T14:23:16ZStroh formalism in analysis of skew-symmetric and symmetric weight functions for interfacial cracksThe focus of the article is on analysis of skew-symmetric weight matrix functions for interfacial cracks in two dimensional anisotropic solids. It is shown that the Stroh formalism proves to be an efficient approach to this challenging task. Conventionally, the weight functions, both symmetric and skew-symmetric, can be identified as a non-trivial singular solutions of the homogeneous boundary value problem for a solid with a crack. For a semi-infinite crack, the problem can be reduced to solving a matrix Wiener-Hopf functional equation. Instead, the Stroh matrix representation of displacements and tractions, combined with a Riemann-Hilbert formulation, is used to obtain an algebraic eigenvalue problem, that is solved in a closed form. The proposed general method is applied to the case of a quasi-static semi-infinite crack propagation between two dissimilar orthotropic media: explicit expressions for the weight matrix functions are evaluated and then used in the computation of complex stress intensity factor corresponding to an asymmetric load acting on the crack faces.Lorenzo Morinilorenzo.morini@imtlucca.itEnrico RadiAlexander MovchanNatalia Movchan2016-03-14T14:17:09Z2016-03-14T14:17:09Zhttp://eprints.imtlucca.it/id/eprint/3227This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32272016-03-14T14:17:09ZIntegral identities for a semi-infinite interfacial crack in anisotropic elastic bimaterialsThe focus of the article is on the analysis of a semi-infinite crack at the interface between two dissimilar anisotropic elastic materials, loaded by a general asymmetrical system of forces acting on the crack faces. Recently derived symmetric and skew-symmetric weight function matrices are introduced for both plane strain and antiplane shear cracks, and used together with the fundamental reciprocal identity (Betti formula) in order to formulate the elastic fracture problem in terms of singular integral equations relating the applied loading and the resulting crack opening. The proposed compact formulation can be used to solve many problems in linear elastic fracture mechanics (for example various classic crack problems in homogeneous and heterogeneous anisotropic media, as piezoceramics or composite materials). This formulation is also fundamental in many multifield theories, where the elastic problem is coupled with other concurrent physical phenomena.Lorenzo Morinilorenzo.morini@imtlucca.itAmdrea PiccolroazGennady MishurisEnrico Radi2016-03-11T13:18:00Z2016-03-11T13:18:00Zhttp://eprints.imtlucca.it/id/eprint/3221This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32212016-03-11T13:18:00ZOn fracture criteria for dynamic crack propagation in elastic materials with couple stressesThe focus of the article is on fracture criteria for dynamic crack propagation in elastic materials with microstructures. Steady-state propagation of a Mode III semi-infinite crack subject to loading applied on the crack surfaces is considered. The micropolar behavior of the material is described by the theory of couple-stress elasticity developed by Koiter. This constitutive model includes the characteristic lengths in bending and torsion, and thus it is able to account for the underlying microstructures of the material. Both translational and micro-rotational inertial terms are included in the balance equations, and the behavior of the solution near to the crack tip is investigated by means of an asymptotic analysis. The asymptotic fields are used to evaluate the dynamic J-integral for a couple-stress material, and the energy release rate is derived by the corresponding conservation law. The propagation stability is studied according to the energy-based Griffith criterion and the obtained results are compared to those derived by the application of the maximum total shear stress criterion.Lorenzo Morinilorenzo.morini@imtlucca.itAmdrea PiccolroazGennady MishurisEnrico Radi2016-03-11T12:45:11Z2016-03-11T12:45:11Zhttp://eprints.imtlucca.it/id/eprint/3219This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32192016-03-11T12:45:11ZWeight function approach to study a crack propagating along a bimaterial interface under asymmetric loading in anisotropic solidsThe focus of this paper is the study of the dynamic steady-state propagation of interfacial cracks in anisotropic bimaterials under general, nonsymmetric loading conditions. Symmetric and skew-symmetric weight functions, defined as singular nontrivial solutions of a homogeneous traction-free crack problem, have been recently derived for a quasistatic semiinfinite crack at the interface between two dissimilar anisotropic materials. In this paper, the expressions for the weight functions are generalized to the case of a dynamic steady-state crack between two anisotropic media. A functional matrix equation, through which it is possible to evaluate the stress intensity factors and the energy release rate at the crack tip, is obtained. A general method for calculating the asymptotic coefficients of the displacement and traction fields, without any restrictions regarding the loading applied on the crack faces, is developed. The proposed approach is applied for the computing stress intensity factors and higher-order asymptotic terms corresponding to two different example loading configurations acting on the crack faces in an orthotropic bimaterial.Lewis PryceLorenzo Morinilorenzo.morini@imtlucca.itGennady Mishuris2016-03-11T12:26:37Z2016-04-06T09:07:16Zhttp://eprints.imtlucca.it/id/eprint/3217This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32172016-03-11T12:26:37ZRemarks on the energy release rate for an antiplane moving crack in couple stress elasticityThis paper is concerned with the steady-state propagation of an antiplane semi-infinite crack in couple stress elastic materials. A distributed loading applied at the crack faces and moving with the same velocity of the crack tip is considered, and the influence of the loading profile variations and microstructural effects on the dynamic energy release rate is investigated. The behavior of both energy release rate and maximum total shear stress when the crack tip speed approaches the critical speed (either that of the shear waves or that of the localized surface waves) is studied. The limit case corresponding to vanishing characteristic scale lengths is addressed both numerically and analytically by means of a comparison with classical elasticity results.Lorenzo Morinilorenzo.morini@imtlucca.itAmdrea PiccolroazGennady Mishuris2016-03-11T12:15:25Z2016-03-11T12:15:25Zhttp://eprints.imtlucca.it/id/eprint/3215This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32152016-03-11T12:15:25ZBoundary integral formulation for interfacial cracks in thermodiffusive bimaterialsAn original boundary integral formulation is proposed for the problem of a semi-infinite crack at the interface between two dissimilar elastic materials in the presence of heat flows and mass diffusion. Symmetric and skew-symmetric weight function matrices are used together with a generalized Betti’s reciprocity theorem in order to derive a system of integral equations that relate the applied loading, the temperature and mass concentration fields, the heat and mass fluxes on the fracture surfaces and the resulting crack opening. The obtained integral identities can have many relevant applications, such as for the modelling of crack and damage processes at the interface between different components in electrochemical energy devices characterized by multi-layered structures (solid oxide fuel cells and lithium ions batteries).Lorenzo Morinilorenzo.morini@imtlucca.itAmdrea Piccolroaz2016-03-11T12:10:25Z2016-05-04T09:55:02Zhttp://eprints.imtlucca.it/id/eprint/3214This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32142016-03-11T12:10:25ZConservation integrals for two circular holes kept at different temperatures in a thermoelastic solidAbstract An explicit analytic solution for thermal stresses in an infinite thermoelastic medium with two circular cylindrical holes of different sizes kept at different constant temperatures, under steady-state heat flux is presented. The solution is obtained by using the most general representation of a biharmonic function in bipolar coordinates. The stress field is decomposed into the sum of a particular stress field induced by the steady-state temperature distribution and an auxiliary isothermal stress field required to satisfy the boundary conditions on the holes. The variations of the stress concentration factor on the surface of the holes are determined for varying geometry of the holes. The concept of the conservation integrals Jk, M and L is extended to steady state thermoelasticity and the integrals are proved to be path-independent. These integrals are calculated on closed contours encircling one or both holes. The geometries of a hole in a half-space and an eccentric annular cylinder are considered as particular cases.Enrico RadiLorenzo Morinilorenzo.morini@imtlucca.itI. Sevostianov2016-03-11T12:02:01Z2016-05-04T09:53:37Zhttp://eprints.imtlucca.it/id/eprint/3212This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/32122016-03-11T12:02:01ZMultiscale asymptotic homogenization analysis of thermo-diffusive composite materialsIn this paper an asymptotic homogenization method for the analysis of composite materials with periodic microstructure in presence of thermodiffusion is described. Appropriate down-scaling relations correlating the microscopic fields to the macroscopic displacements, temperature and chemical potential are introduced. The effects of the material inhomogeneities are described by perturbation functions derived from the solution of recursive cell problems. Exact expressions for the overall elastic and thermodiffusive constants of the equivalent first order thermodiffusive continuum are derived. The proposed approach is applied to the case of a two-dimensional bi-phase orthotropic layered material, where the effective elastic and thermodiffusive properties can be determined analytically. Considering this illustrative example and assuming periodic body forces, heat and mass sources acting on the medium, the solution performed by the first order homogenization approach is compared with the numerical results obtained by the heterogeneous model.Andrea Bacigalupoandrea.bacigalupo@imtlucca.itLorenzo Morinilorenzo.morini@imtlucca.itAmdrea Piccolroaz2015-01-21T09:53:35Z2016-03-11T12:17:52Zhttp://eprints.imtlucca.it/id/eprint/2544This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/25442015-01-21T09:53:35ZEffective elastic properties of planar SOFCs: a non-local dynamic homogenization approachAbstract The focus of the article is on the analysis of effective elastic properties of planar Solid Oxide Fuel Cell (SOFC) devices. An ideal periodic multi-layered composite (SOFC-like) reproducing the overall properties of multi-layer {SOFC} devices is defined. Adopting a non-local dynamic homogenization method, explicit expressions for overall elastic moduli and inertial terms of this material are derived in terms of micro-fluctuation functions. These micro-fluctuation functions are then obtained solving the cell problems by means of finite element techniques. The effects of the temperature variation on overall elastic and inertial properties of the fuel cells are studied. Dispersion relations for acoustic waves in SOFC-like multilayered materials are derived as functions of the overall constants, and the results obtained by the proposed computational homogenization approach are compared with those provided by rigorous Floquet–Bloch theory. Finally, the influence of the temperature and of the elastic properties variation on the Bloch spectrum is investigated.Andrea Bacigalupoandrea.bacigalupo@imtlucca.itLorenzo Morinilorenzo.morini@imtlucca.itAmdrea Piccolroaz