Modeling Group

@article{vanaei_2061,

title = {Numerical-Experimental Analysis toward the Strain Rate Sensitivity of 3D-Printed Nylon Reinforced by Short Carbon Fiber},

author = {Hamidreza Vanaei and Anouar El Magri and Mohammadali Rastak and Saeedeh Vanaei and Sébastien Vaudreuil and Abbas Tcharkhtchi},

url = {https://doi.org/10.3390/ma15248722},

year  = {2022},

date = {2022-12-01},

journal = {Materials},

volume = {15},

number = {24},

pages = {8722},

abstract = {Despite the application of the Additive Manufacturing process and the ability of parts' construction directly from a 3D model, particular attention should be taken into account to improve their mechanical characteristics. In this paper, we present the effect of individual process variables and the strain-rate sensitivity of Onyx (Nylon mixed with chopped carbon fiber) manufactured by Fused Filament Fabrication (FFF), using both experimental and simulation manners. The main objective of this paper is to present the effect of the selected printing parameters (print speed and platform temperature) and the sensitivity of the 3D-printed specimen to the strain rate during tensile behavior. A strong variation of tensile behavior for each set of conditions has been observed during the quasi-static tensile test. The variation of 40 °C in the platform temperature results in a 10% and 11% increase in Young's modulus and tensile strength, and 8% decrease in the failure strain, respectively. The variation of 20 mm·s?1 in print speed results in a 14% increase in the tensile strength and 11% decrease in the failure strain. The individual effect of process variables is inevitable and affects the mechanical behavior of the 3D-printed composite, as observed from the SEM micrographs (ductile to brittle fracture). The best condition according to their tensile behavior was chosen to investigate the strain rate sensitivity of the printed specimens both experimentally and using Finite Element (FE) simulations. As observed, the strain rate clearly affects the failure mechanism and the predicted behavior using the FE simulation. Increase in the elongation speed from 1 mm·min?1 to 100 mm·min?1, results in a considerable increase in Young's modulus. SEM micrographs demonstrated that although the mechanical behavior of the material varied by increasing the strain rate, the failure mechanism altered from ductile to brittle failure.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{vaudreuil_2062,

title = {Effects of Power and Laser Speed on the Mechanical Properties of AlSi7Mg0.6 Manufactured by Laser Powder Bed Fusion},

author = {Sébastien Vaudreuil and Salah Eddine Bencaid and Hamidreza Vanaei and Anouar El Magri},

url = {https://doi.org/10.3390/ma15238640},

year  = {2022},

date = {2022-12-01},

journal = {Materials},

volume = {15},

number = {23},

pages = {8640},

abstract = {The AlSi7Mg0.6 alloy, with its good tolerance against strain, is used in laser powder bed fusion (LPBF) to produce parts with complex geometries for aerospace engineering. Production of parts with good mechanical strength requires, however, the optimization of laser parameters. This study thus evaluated the influence of scanning speed, laser power, and strategy on several mechanical properties (tensile/resilience/hardness) to identify an optimal processing region. Results have shown the profound influence of laser power and scanning speed on mechanical properties, with a limited influence from the laser strategy. Tensile strength values ranging from 122 to 394 MPa were obtained, while Young's Modulus varied from 17 to 29 GPa, and the elongation at break ranged from 2.1 to 9.8%. Surface plots of each property against laser power and speed revealed a region of higher mechanical properties. This region is found when using 50 µm thick layers for energy densities between 25 and 35 J/mm3. Operating at higher values of energy density yielded sub-optimal properties, while a lower energy density resulted in poor performances. Results have shown that any optimization strategy must not only account for the volumic energy density value, but also for laser power itself when thick layers are used for fabrication. This was shown through parts exhibiting reduced mechanical performances that were produced within the optimal energy density range, but at low laser power. By combining mid-speed and power within the optimal region, parts with good microstructure and limited defects such as balling, keyhole pores, and hot cracking will be produced. Heat-treating AlSi7Mg0.6 parts to T6 temper negatively affected mechanical performances. Adapted tempering conditions are thus required if improvements are sought through tempering.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{bottino_2298,

title = {Time evolution and finite element representation of Phase Space Zonal Structures in ORB5},

author = {Alberto Bottino and Matteo Valerio Falessi and Thomas Hayward-Schneider and Alessandro Biancalani and Sergio Briguglio and R Hatzky and Philipp Lauber and Alexey Mishchenko and Emanuele Poli and B Rettino and Francesco Vannini and Xin Wang and Fulvio Zonca},

url = {https://dx.doi.org/10.1088/1742-6596/2397/1/012019},

year  = {2022},

date = {2022-12-01},

journal = {Journal of Physics: Conference Series},

volume = {2397},

pages = {012019},

abstract = {Phase Space Zonal Structures (PSZSs), obtained by averaging out dependencies on angle-like variables in the energetic particle (EP) distribution function, play a fundamental role in regulating EP transport induced by Alfvén instabilities in burning plasmas, acting as a slowly varying nonlinear equilibrium state. Therefore, they are of great interest for the development of reduced models for the description of EP heat and particle transport on long time scales, comparable with the energy confinement time, for future burning plasma experiments. In this work, we propose an efficient finite element based projection of the time evolution of the PSZS, suited for global particle-in-cell (PIC) gyrokinetic (GK) codes. The resulting algorithm has been implemented in the global GK PIC code ORB5. PSZSs can not only be used for validating reduced models, but also as a diagnostic tool for characterizing the nonlinear interaction in phase space between Alfvén instabilities and EPs in global GK simulations.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{vannini_2300,

title = {Gyrokinetic modelling of the Alfvén mode and EGAM activity in ASDEX Upgrade},

author = {Francesco Vannini and Alessandro Biancalani and Alberto Bottino and Thomas Hayward-Schneider and Philipp Lauber and Alexey Mishchenko and Emanuele Poli and B Rettino and Gregorio Vlad and Xin Wang and ASPEX Upgrade Team},

url = {https://dx.doi.org/10.1088/1742-6596/2397/1/012003},

year  = {2022},

date = {2022-12-01},

journal = {Journal of Physics: Conference Series},

volume = {2397},

pages = {012003},

abstract = {Energetic particles present in tokamak machines can drive through resonant wave-particle interaction different plasma instabilities, e.g Alfvén modes and energetic particle-driven geodesic acoustic modes (EGAMs). While the former are potentially detrimental as they can enhance the energetic particle transport and damage the machine wall, the latter are axisymmetric, possibly benign modes that can act to regulate turbulence. A unique scenario, the so-called NLED-AUG case, has been developed in ASDEX Upgrade by tuning the plasma parameters so that the energetic particle kinetic energy is 100 times higher than that of the background plasma, like in ITER. An intense energetic particle-driven activity is observed, most prominently various Alfvén mode bursts triggering chirping EGAMs. The present work reports studies on the Alfvén mode and EGAM dynamics showing, for the first time, many toroidal mode gyrokinetic simulations with ORB5 where the NLED-AUG case scenario is considered. We study the mode dynamics modelling the energetic particles with different equilibrium distribution functions, such as: isotropic slowing-down, double-bump-on-tail and equivalent Maxwellian. We retain, at the beginning, the nonlinearities only in the energetic particle dynamics. Later, also the background plasma species nonlinearities are taken into account.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ouassil_2046,

title = {Investigating the effect of printing conditions and annealing on the porosity and tensile behavior of 3D-printed polyetherimide material in Z-direction},

author = {Salah-Eddine Ouassil and Anouar El Magri and Hamidreza Vanaei and Sébastien Vaudreuil},

url = {https://doi.org/10.1002/app.53353},

year  = {2022},

date = {2022-11-01},

journal = {Journal Of Applied Polymer Science},

volume = {140},

number = {4},

pages = {e53353},

abstract = {Fused filament fabrication process presents drawbacks in mechanical properties observed when printing in the build direction (Z-direction). Such anisotropic properties will affect the part's performances and have to be minimized during fabrication. This study aims to evaluate the effects of nozzle temperature, printing speed and specimen state (annealed or as-printed) on porosity percentage and tensile properties for 3D printed polyetherimide (PEI) (ULTEM 1010) parts in Z-direction. The results demonstrated that print speed is the most influential process parameter that should be adjusted in consideration with the other printing parameters. The specimens' state did not reveal a noticeable influence, as the amorphous nature of PEI is considered less receptive to annealing. The optimization method to achieve the best results yielded values of 360 °C and 30 mm/s as printing conditions, followed by heat treatment. This was confirmed by porosity measurements, tensile testing, and scanning electron microscopy observations. The best performances of PEI material were 3425.5 MPa, 102 MPa, and 4.30% for Young's modulus, tensile strength, and elongation at break, respectively.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{vannini_2299,

title = {Gyrokinetic modelling of the Alfvén mode activity in ASDEX Upgrade with an isotropic slowing-down fast-particle distribution},

author = {Francesco Vannini and Alessandro Biancalani and Alberto Bottino and Thomas Hayward-Schneider and Philipp Lauber and Alexey Mishchenko and Emanuele Poli and B Rettino and Gregorio Vlad and Xin Wang and ASPEX Upgrade Team},

url = {https://dx.doi.org/10.1088/1741-4326/ac8b1e},

year  = {2022},

date = {2022-11-01},

journal = {Nuclear Fusion},

volume = {62},

number = {12},

pages = {126042},

abstract = {In the present paper, the evolution of the Alfvén modes (AMs) is studied in a realistic ASDEX Upgrade equilibrium by analyzing the results of simulations with the global, electromagnetic, gyrokinetic particle-in-cell code ORB5. The energetic particles (EPs) are modelled both via the newly implemented isotropic slowing-down and with Maxwellian distribution functions. The comparison of the numerical results shows that modelling the EPs with the equivalent Maxwellian rather than with the slowing-down, does not significantly affect the frequency of the driven AM, while its growth rate appears to be underestimated with a quantitative difference as large as almost 30%. Additionally the choice of the isotropic slowing-down allows a better description of the nonlinear modification of the dominant AM frequency, while an equivalent Maxwellian underestimates it. A good comparison with the experimental spectrogram is found.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{benmesbah_1960,

title = {Calorimetric study of carbon dioxide (CO2) hydrate formation and dissociation processes in porous media},

author = {Fatima Benmesbah and Pascal Clain and Olivia Fandino and Véronique Osswald and Laurence Fournaison and Christophe Dicharry and Anthony Delahaye},

url = {https://www.sciencedirect.com/science/article/pii/S0009250922006923},

year  = {2022},

date = {2022-10-01},

journal = {Chemical Engineering Science},

volume = {264},

pages = {118108},

abstract = {Understanding the formation and dissociation mechanisms of gas hydrate in porous media is important for the development of new energy-efficient and environmentally friendly technologies related to cold storage as they provide significant latent heat and energy density at suitable phase change temperature. The challenge is to understand the interactions between gas hydrates and the chosen storage media in order to assess the operating conditions likely to optimize time and energy consumption in cold production and storage systems. In this work, CO2 hydrates formation and dissociation are investigated in two morphologically different porous materials: sand and silica gels. A calorimetric approach is applied to study both the CO2 hydrate formation kinetics, particularly the induction time, and the amount of hydrate formed for each of the two porous materials. The experiments are performed using a differential thermal analysis device with two identical measuring cells. The present work is focused on assessing the effect of key factors like water saturation, particle size and the morphology of porous media on CO2 hydrate formation and dissociation processes. Overall, the results do not show a statistically significant correlation between these factors and the induction time. Interestingly, the results obtained with dual porous silica gel showed a higher amount of hydrate formed compared to those with sand for similar initial pressure, temperature and water content conditions. This result may be due to the fact that silica gels provide higher surface area due to their smaller particle size (20-45 µm vs 80-450 µm for sand), and the presence of internal pore volume in silica gel particles.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{vanaei_1962,

title = {Roadmap: Numerical-Experimental Investigation and Optimization of 3D-Printed Parts Using Response Surface Methodology},

author = {Hamidreza Vanaei and Sofiane Khelladi and Abbas Tcharkhtchi},

url = {https://www.mdpi.com/1996-1944/15/20/7193},

year  = {2022},

date = {2022-10-01},

journal = {Materials},

volume = {15},

number = {20},

pages = {7193},

abstract = {Several process variables can be taken into account to optimize the fused filament fabrication (FFF) process, a promising additive manufacturing technique. To take into account the most important variables, a numerical-experimental roadmap toward the optimization of the FFF process, by taking into account some physico-chemical and mechanical characteristics, has been proposed to implement the findings through the thermal behavior of materials. A response surface methodology (RSM) was used to consider the effect of liquefier temperature, platform temperature, and print speed. RSM gave a confidence domain with a high degree of crystallinity, Young's modulus, maximum tensile stress, and elongation at break. Applying the corresponding data from the extracted zone of optimization to the previously developed code showed that the interaction of parameters plays a vital role in the rheological characteristics, such as temperature profile of filaments during deposition. Favorable adhesion could be achieved through the deposited layers in the FFF process. The obtained findings nurture motivations for working on the challenges and bring us one step closer to the optimization objectives in the FFF process to solve the industrial challenges.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{venkateswaran_2384,

title = {Stability analysis of tensegrity mechanism coupled with a bio-inspired piping inspection robot},

author = {Swaminath Venkateswaran and Damien Charles Chablat},

url = {https://www.tandfonline.com/doi/abs/10.1080/10255842.2022.2116885},

year  = {2022},

date = {2022-10-01},

journal = {Computer Methods In Biomechanics And Biomedical Engineering},

volume = {25},

number = {1},

pages = {300-302},

abstract = {Piping inspection robots play an essential role for industries as they can reduce the human effort and pose lesser risker to their lives. Generally, the locomotion techniques of these robots can be classified into mechanical and bioinspired. By using slot-follower leg mechanisms, DC-motors and control units, a rigid caterpillar type inspection robot was  designed  and  developed  at  LS2N,  France. This rigid prototype helped in identifying the static forces required to accomplish good contact forces with the pipeline walls. In order to work inside curvatures, a tensegrity mechanism that uses three tension springs and a passive  universal  joint  was  introduced  between  each module of this robot. The optimal parameters of the robot assembly were identified by considering a preloading along the cables, which ensured the stability of the entire robot. However, under static conditions, there exists some forces on the robot,especially on the tensegrity mechanism when one end of the leg mechanisms is clamped with the pipeline walls. These forces are dominant when the orientation of the pipeline is horizontal. The objective of this article is to understand the effect of stiffness of thespring on the static stability of the tensegrity mechanism under the self-weight of the robot assembly.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{el_magri_1958,

title = {Effects of Laser Power and Hatch Orientation on Final Properties of PA12 Parts Produced by Selective Laser Sintering},

author = {Anouar El Magri and Hamidreza Vanaei and Salah Eddine Bencaid and Sébastien Vaudreuil},

url = {https://doi.org/10.3390/polym14173674},

year  = {2022},

date = {2022-09-01},

journal = {Polymers},

volume = {14},

number = {17},

pages = {3674},

abstract = {Poly(dodecano-12-lactam) (commercially known as polyamide ?PA12?) is one of the most resourceful materials used in the selective laser sintering (SLS) process due to its chemical and physical properties. The present work examined the influence of two SLS parameters, namely, laser power and hatch orientation, on the tensile, structural, thermal, and morphological properties of the fabricated PA12 parts. The main objective was to evaluate the suitable laser power and hatching orientation with respect to obtaining better final properties. PA12 powders and SLS-printed parts were assessed through their particle size distributions, X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), a scanning electron microscope (SEM), and their tensile properties. The results showed that the significant impact of the laser power while hatching is almost unnoticeable when using a high laser power. A more significant condition of the mechanical properties is the uniformity of the powder bed temperature. Optimum factor levels were achieved at 95% laser power and parallel/perpendicular hatching. Parts produced with the optimized SLS parameters were then subjected to an annealing treatment to induce a relaxation of the residual stress and to enhance the crystallinity. The results showed that annealing the SLS parts at 170 °C for 6 h significantly improved the thermal, structural, and tensile properties of 3D-printed PA12 parts.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{el_magri_1892,

title = {Effects of Laser Power and Hatch Orientation on Final Properties of PA12 Parts Produced by Selective Laser Sintering},

author = {Anouar El Magri and Salah Eddine Bencaid and Hamidreza Vanaei and Sébastien Vaudreuil},

url = {https://www.mdpi.com/2073-4360/14/17/3674},

year  = {2022},

date = {2022-09-01},

journal = {Polymers},

volume = {14},

number = {17},

pages = {3674},

abstract = {Poly(dodecano-12-lactam) (commercially known as polyamide ?PA12?) is one of the most resourceful materials used in the selective laser sintering (SLS) process due to its chemical and physical properties. The present work examined the influence of two SLS parameters, namely, laser power and hatch orientation, on the tensile, structural, thermal, and morphological properties of the fabricated PA12 parts. The main objective was to evaluate the suitable laser power and hatching orientation with respect to obtaining better final properties. PA12 powders and SLS-printed parts were assessed through their particle size distributions, X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), a scanning electron microscope (SEM), and their tensile properties. The results showed that the significant impact of the laser power while hatching is almost unnoticeable when using a high laser power. A more significant condition of the mechanical properties is the uniformity of the powder bed temperature. Optimum factor levels were achieved at 95% laser power and parallel/perpendicular hatching. Parts produced with the optimized SLS parameters were then subjected to an annealing treatment to induce a relaxation of the residual stress and to enhance the crystallinity. The results showed that annealing the SLS parts at 170 °C for 6 h significantly improved the thermal, structural, and tensile properties of 3D-printed PA12 parts},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{boudin_1894,

title = {A kinetic model of polyatomic gas with resonant collisions},

author = {Laurent Boudin and Alex Rossi and Francesco Salvarani},

url = {https://doi.org/10.1007/s11587-022-00733-1},

year  = {2022},

date = {2022-09-01},

journal = {Ricerche Di Matematica},

keywords = {},

pubstate = {online},

tppubtype = {article}

}

@article{mishchenko_2296,

title = {Gyrokinetic particle-in-cell simulations of electromagnetic turbulence in the presence of fast particles and global modes},

author = {Alexey Mishchenko and Alberto Bottino and Thomas Hayward-Schneider and Emanuele Poli and Xin Wang and C Nührenberg and Alessandro Biancalani and E Lanti and Philipp Lauber and R Hatzky and Francesco Vannini and Laurent Villard and F Widmer and R Keiber},

url = {https://dx.doi.org/10.1088/1361-6587/ac8dbc},

year  = {2022},

date = {2022-09-01},

journal = {Plasma Physics And Controlled Fusion},

volume = {64},

number = {10},

pages = {104009},

abstract = {Global simulations of electromagnetic turbulence in circular-flux-surface tokamak and ASDEX-Upgrade geometry, tearing instabilities and their combination with the electromagnetic turbulence, nonlinear Alfvénic modes in the presence of fast particles and their combination with the electromagnetic turbulence and global electromagnetic turbulence in Wendelstein 7-X stellarator geometry are carried out using the gyrokinetic particle-in-cell code ORB5 (Lanti et al 2020 Comp. Phys. Comm. 251 107072) and EUTERPE (Kornilov et al 2004 Phys. Plasmas 11 3196). Computational feasibility of simulating such complex coupled systems is demonstrated. For simplicity, the reduced mass ratio is used throughout the paper.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{salhi_1885,

title = {Well-posedness and numerical approximation of steady convection-diffusion-reaction problems in porous media},

author = {Loubna Salhi and Mohammed Seaid and Driss Yakoubi},

url = {https://www.sciencedirect.com/science/article/abs/pii/S0898122122003443},

year  = {2022},

date = {2022-08-01},

journal = {Computers & Mathematics With Applications},

volume = {124},

pages = {129-148},

abstract = {We study a class of steady nonlinear convection-diffusion-reaction problems in porous media. The governing equations consist of coupling the Darcy equations for the pressure and velocity fields to two equations for the heat and mass transfer. The viscosity and diffusion coefficients are assumed to be nonlinear depending on the temperature and concentration of the medium. Well-posedness of the coupled problem is analyzed and existence along with uniqueness of the weak solution is investigatedbased on a fixed-point method. An iterative scheme for solving the associated fixed-point problem is proposed and its convergence is studied. Numerical experiments are presented for two examples of coupled convection-diffusion-reaction problems. Applications to radiative heat transfer and propagation of thermal fronts in porous media are also included in this study. The obtained results show good numerical convergence and validate the established theoretical estimates.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{el-amrani_1887,

title = {An iterative scheme for solving acoupled Darcy-convection-diffusion model},

author = {Mofdi El-Amrani and Loubna Salhi and Mohammed Seaid and Driss Yakoubi},

url = {https://www.sciencedirect.com/science/article/pii/S0022247X22006175},

year  = {2022},

date = {2022-08-01},

journal = {Journal Of Mathematical Analysis And Applications},

volume = {517},

number = {2},

pages = {126603},

abstract = {We present an iterative scheme for the numerical analysis of a class of coupled Darcy-convection-diffusion problems modelling flow and heat transfer in porous media. The governing equations consist of the Darcy equations for the flow coupled to a convection-diffusion equation for heat transfer with nonlinear viscosity and diffusion coefficient depending on the temperature. Existence and uniqueness of the weak solution for the considered problem are first analyzed using a fixed-point method and then convergence study of two iterative schemes for the fixed-point algorithm is presented. Two numerical examples are selected to validate the theoretical estimates and to demonstrate the performance of the proposed algorithm. The obtained results support our theoretical expectations for a good numerical convergence with the developed estimates.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{amirat_1963,

title = {Homogenization of MHD flows in porous media},

author = {Youcef Amirat and Kamel Hamdache and Vladimir V. Shelukhin},

url = {https://doi.org/10.1016/j.jde.2022.08.014},

year  = {2022},

date = {2022-08-01},

journal = {Journal Of Differential Equations},

volume = {339},

number = {339},

pages = {90-133},

abstract = {The paper is concerned with the homogenization of a nonlinear differential system describing the flow of an electrically conducting, incompressible and viscous Newtonian fluid through a periodic porous medium, in the presence of a magnetic field. We introduce a variational formulation of the differential system equipped with boundary conditions. We show the existence of a solution of the variational problem, and derive uniform estimates of the solutions depending on the characteristic parameters of the flow. Using the two-scale convergence method, we rigorously derive a two-scale equation for the two-scale current density, and a two-pressure Stokes system. We derive, in the case of constant magnetic permeability, an explicit relation expressing the macroscopic velocity as a function of the macroscopic Lorentz force, the pressure gradient, the external body force, and the macroscopic current density, via two permeability filtration ten- sors. When the magnetic field is absent, this relation reduces to the Darcy law.

© 2022 Elsevier Inc. All rights reserved.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{joseph_1864,

title = {Mechanical Properties and Damage Behavior of Polypropylene Composite (GF50-PP) Plate Fabricated by Thermocompression Process Under High Strain Rate Loading at Room and Cryogenic Temperatures},

author = {Fitoussi Joseph and Mohammad Hossein Nikooharf and Achraf Kallel and Mohammadali Shirinbayani},

url = {https://link.springer.com/article/10.1007/s10443-022-10047-y},

year  = {2022},

date = {2022-07-01},

journal = {Applied Composite Materials},

volume = {29},

number = {3},

pages = {1-21},

abstract = {This paper concerns the coupling effect of strain rate and temperature on the damage mechanical properties of the long-glass-fiber-reinforced polypropylene (GF50-PP) composite produced by the thermocompression process. Composite plates of GF50-PP have been employed to study the effect of glass fiber distribution on the mechanical properties of the composites. To achieve this objective the tensile tests have been performed at strain rate range from quasi-static to 100 s?1 at two loading temperatures of 20 °C and -70 °C, while measuring the local deformation through a contactless technique using a high-speed camera. High strain rate tensile tests findings showed that GF50-PP behavior is strongly strain-rate dependent. For instance, the stress damage threshold for three fiber orientations of 0°, 45°, and 90° to the Mold Flow Direction (MFD) was increased, when the strain rate varies from quasi-static (0.001 s?1) to 100 s?1 at two loading temperatures of 20 °C and -70 °C. The experimental methodology was coupled to microscopic observations using SEM to study the damage mechanisms of GF50-PP. The analysis confirms that there are three damage mechanisms: fiber-matrix interface debonding, matrix breakage, and pseudo-delamination between neighboring bundles of fibers.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{fitoussi_1864,

title = {Mechanical Properties and Damage Behavior of Polypropylene Composite (GF50-PP) Plate Fabricated by Thermocompression Process Under High Strain Rate Loading at Room and Cryogenic Temperatures},

author = {Joseph Fitoussi and Mohammad Hossein Nikooharf and Achraf Kallel and Mohammadali Shirinbayani},

url = {https://link.springer.com/article/10.1007/s10443-022-10047-y},

year  = {2022},

date = {2022-07-01},

journal = {Applied Composite Materials},

volume = {29},

number = {3},

pages = {1-21},

abstract = {This paper concerns the coupling effect of strain rate and temperature on the damage mechanical properties of the long-glass-fiber-reinforced polypropylene (GF50-PP) composite produced by the thermocompression process. Composite plates of GF50-PP have been employed to study the effect of glass fiber distribution on the mechanical properties of the composites. To achieve this objective the tensile tests have been performed at strain rate range from quasi-static to 100 s?1 at two loading temperatures of 20 °C and -70 °C, while measuring the local deformation through a contactless technique using a high-speed camera. High strain rate tensile tests findings showed that GF50-PP behavior is strongly strain-rate dependent. For instance, the stress damage threshold for three fiber orientations of 0°, 45°, and 90° to the Mold Flow Direction (MFD) was increased, when the strain rate varies from quasi-static (0.001 s?1) to 100 s?1 at two loading temperatures of 20 °C and -70 °C. The experimental methodology was coupled to microscopic observations using SEM to study the damage mechanisms of GF50-PP. The analysis confirms that there are three damage mechanisms: fiber-matrix interface debonding, matrix breakage, and pseudo-delamination between neighboring bundles of fibers.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{montiel_1922,

title = {Effect of architecture disorder on the elastic response of two-dimensional lattice materials},

author = {Antoine Montiel and Thuy Nguyen and Cindy Rountree and Valérie Geertsen and Patrick Guenoun and Daniel Bonamy},

url = {https://journals.aps.org/pre/abstract/10.1103/PhysRevE.106.015004?ft=1},

year  = {2022},

date = {2022-07-01},

journal = {Physical Review E},

volume = {106},

number = {1},

pages = {015004},

abstract = {We examine how disordering joint position influences the linear elastic behavior of lattice materials via numerical simulations in two-dimensional beam networks. Three distinct initial crystalline geometries are selected as representative of mechanically isotropic materials with low connectivity, mechanically isotropic materials with high connectivity, and mechanically anisotropic materials with intermediate connectivity. Introducing disorder generates spatial fluctuations in the elasticity tensor at the local (joint) scale. Proper coarse-graining reveals a well-defined continuum-level scale elasticity tensor. Increasing disorder aids in making initially anisotropic materials more isotropic. The disorder impact on the material stiffness depends on the lattice connectivity: Increasing the disorder softens lattices with high connectivity and stiffens those with low connectivity, without modifying the scaling between elastic modulus and density (linear scaling for high connectivity and cubic scaling for low connectivity). Introducing disorder in lattices with intermediate fixed connectivity reveals both scaling: the linear scaling occurs for low density, the cubic one at high density, and the crossover density increases with disorder. Contrary to classical formulations, this work demonstrates that connectivity is not the sole parameter governing elastic modulus scaling. It offers a promising route to access novel mechanical properties in lattice materials via disordering the architectures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{levy_1924,

title = {DevOps Model Appproach for Monitoring Smart Energy Systems},

author = {Loup-Noé Levy and Jérémie Bosom and Guillaume Guérard and Sofiane Ben Amor and Marc Bui and Hai Tran},

url = {https://www.mdpi.com/1996-1073/15/15/5516},

year  = {2022},

date = {2022-07-01},

journal = {Energies},

volume = {15},

number = {15},

pages = {5516},

abstract = {Energy systems are often socio-technical complex systems that are facing new challenges regarding technological and environmental changes. Because of their complex nature, they cannot be approached solely through analytical modeling, hence the inefficiency of most classical modeling approaches. In this article, a Hybrid Approach based on both systemic and analytical modeling is presented and applied to a case study. From this novel approach, a model?the Multi-Institution Building Energy System?is presented. It allowed us to highlight and detail the need for greater governance of energy systems. The socio-technical solutions identified to answer the issues of governance (Accuracy, Reliability and Fairness) were DevOps methodology and the use of Distributed Microservices Architecture. Based on this framework, the design of a Decision Support System assuring and exploiting state-of-the-art scalable tools for data management and machine learning factories is described in this article. Moreover, we wish to set up the conceptual basis necessary for the design of a generic theoretical framework of optimization applicable to complex socio-technical systems in the context of the management of a shared resource.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{m._himeur_2099,

title = {Towards an Accurate Aerodynamic Performance Analysis Methodology of Cross-Flow Fans},

author = {Rania M. Himeur and Sofiane Khelladi and Mohamed Abdessamed Ait Chikh and Hamidreza Vanaei and Idir Belaidi and Farid Bakir},

url = {https://doi.org/10.3390/en15145134},

year  = {2022},

date = {2022-07-01},

journal = {Energies},

volume = {15},

number = {14},

pages = {5134},

abstract = {Cross-flow fans (CFFs) have become increasingly popular in recent years. This is due to their use in several domains such as air conditioning and aircraft propulsion. They also show their utility in the ventilation system of hybrid electric cars. Their high efficiency and performance significantly rely on the design parameters. Up to now, there is no general approach that predicts the CFFs' performance. This work describes a new methodology that helps deduce the performance of CFFs in turbomachinery, using both analytical modeling and experimental data. Two different loss models are detailed and compared to determine the performance-pressure curves of this type of fan. The efficiency evaluation is achieved by realizing a multidisciplinary study, computational fluid dynamics (CFD) simulations, and an optimization algorithm combined to explore the internal flow field and obtain additional information about the eccentric vortex, to finally obtain the ultimate formulation of the Eck/Laing CFF efficiency, which is validated by the experimental results with good agreement. This approach can be an efficient tool to speed up the cross-flow fans' design cycle and to predict their global performance.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ben_abdallah_1721,

title = {Modeling of viscoelastic behavior of a shape memory polymer blend},

author = {Abir Ben Abdallah and Achraf Kallel and Abbas Tcharkhtchi and Tarek Hassine and Fehmi Gamaoun},

url = {https://onlinelibrary.wiley.com/doi/10.1002/app.51859},

year  = {2022},

date = {2022-05-01},

journal = {Journal Of Applied Polymer Science},

volume = {139},

number = {13},

pages = {51859},

abstract = {Shape memory effect (SME) of polymers is a property that concerns both,

macroscopic and microscopic changes. The variation of internal polymer

properties such, as molecular weight (Mw), rigidity, and viscoelasticity could

alter its SME. In this study, a bi-parabolic model with six parameters is used to

describe the viscoelastic behavior of a shape memory polymer (SMP) blend

(40% poly(caprolactone), PCL/60% Styrene-Butadiene-Styrene) with different

PCL Mw. These parameters are determined using the Cole-Cole method.

Modeling curves (E00 = f (E0)) will be then compared to experimental data from

dynamical mechanical analysis (DMA) tests. It is shown that the bi-parabolic

model predicts well the behavior of the SMP mixture for different Mw of PCL.

Afterwards, the evolution of the model parameters with the Mw of PCL is

investigated. It is revealed that, when Mw of PCL drops, the relaxation modulus

E0 increases. This result proves that the rigidity of the SMP blend rises with

Mw declines.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{boudin_1819,

title = {Exponential Convergence Towards Consensus for Non-Symmetric Linear First-Order Systems in Finite and Infinite Dimensions},

author = {Laurent Boudin and Francesco Salvarani and Emmanuel Trélat},

url = {https://epubs.siam.org/doi/abs/10.1137/21M1416102},

year  = {2022},

date = {2022-05-01},

journal = {Siam Journal On Mathematical Analysis},

volume = {54},

number = {3},

pages = {2727-2752},

abstract = {We consider finite and infinite-dimensional first-order consensus systems with time- constant interaction coefficients. For symmetric coefficients, convergence to consensus is classically established by proving, for instance, that the usual variance is an exponentially decreasing Lyapunov function. We investigate here the convergence to consensus in the non-symmetric case: we identify a positive weight which allows us to define a weighted mean corresponding to the consensus and obtain exponential convergence towards consensus. Moreover, we compute the sharp exponential decay rate.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{taleb_1836,

title = {A Flexible Deep Learning Method for Energy Forecasting},

author = {Ihab Taleb and Guillaume Guérard and Nga Nguyen and Frédéric Fauberteau},

url = {https://www.mdpi.com/1996-1073/15/11/3926},

year  = {2022},

date = {2022-05-01},

journal = {Energies},

volume = {15},

number = {11},

pages = {3926},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{rettino_2297,

title = {Gyrokinetic modeling of anisotropic energetic particle driven instabilities in tokamak plasmas},

author = {B Rettino and Thomas Hayward-Schneider and Alessandro Biancalani and Alberto Bottino and I Chavdarovski and M Weiland and Francesco Vannini and F Jenko and Philipp Lauber},

url = {https://dx.doi.org/10.1088/1741-4326/ac6680},

year  = {2022},

date = {2022-05-01},

journal = {Nuclear Fusion},

volume = {62},

number = {7},

pages = {076027},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{maarouf_1803,

title = {Characteristics/finite element analysis for two incompressible fluid flows with surface tension using level set method},

author = {Sarra Maarouf and Christine Bernardi and Driss Yakoubi},

url = {https://www.sciencedirect.com/science/article/pii/S0045782522001530},

year  = {2022},

date = {2022-03-01},

journal = {Computer Methods In Applied Mechanics And Engineering},

volume = {394},

pages = {114843},

abstract = {In this paper, we present and analyze a finite element level set method based on the method of characteristics for two phase

flow. Surface tension effects are taken into account by the CSF approach. We first write the variational formulation of the problem and investigate its well-posedness. Next, for the discretization, a first order method of characteristics approach for the

evolution of the level set function and for the material derivative of the velocity is used. The velocity and pressure unknowns

are discretized by P2? P1 Taylor-Hood finite elements. Then, in each time step, the interface transport is decoupled from the

Navier-Stokes equations. Well-posedness results for subproblems in this decoupled discrete problem are derived. Furthermore,

under high regularity assumptions, we state error estimates for our scheme. Ultimately, three computational examples illustrate

the performance of the proposed method.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{gueye_thiam_2098,

title = {3D Printed and Conventional Membranes?A Review},

author = {Baye Gueye Thiam and Anouar El Magri and Hamidreza Vanaei and Sébastien Vaudreuil},

url = {https://doi.org/10.3390/polym14051023},

year  = {2022},

date = {2022-03-01},

journal = {Polymers},

volume = {14},

number = {5},

pages = {1023},

abstract = {Polymer membranes are central to the proper operation of several processes used in a wide range of applications. The production of these membranes relies on processes such as phase inversion, stretching, track etching, sintering, or electrospinning. A novel and competitive strategy in membrane production is the use of additive manufacturing that enables the easier manufacture of tailored membranes. To achieve the future development of better membranes, it is necessary to compare this novel production process to that of more conventional techniques, and clarify the advantages and disadvantages. This review article compares a conventional method of manufacturing polymer membranes to additive manufacturing. A review of 3D printed membranes is also done to give researchers a reference guide. Membranes from these two approaches were compared in terms of cost, materials, structures, properties, performance. and environmental impact. Results show that very few membrane materials are used as 3D-printed membranes. Such membranes showed acceptable performance, better structures, and less environmental impact compared with those of conventional membranes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}