Modeling Group

@article{samah_2410,

title = {Investigation of ice detachment by a liquid jet on various submerged surfaces for the development of ice slurry generators without mechanical scraping},

author = {Walid Samah and Pascal Clain and François Rioual and Laurence Fournaison and Anthony Delahaye},

url = {https://www.sciencedirect.com/science/article/pii/S1359431123014928},

year  = {2024},

date = {2024-01-01},

journal = {Applied Thermal Engineering},

volume = {236},

pages = {121463},

abstract = {Ice slurry is an alternative method to reduce the quantity and emission of greenhouse refrigerants, as well as control electrical energy consumption. However, the production of ice slurry requires the use of scraped-surface generators, which are costly to maintain and consume high mechanical energy. Therefore, studying the icephobic behavior of surfaces is of interest to significantly reduce ice adhesion and facilitate detachment without the need for mechanical scrapers. This study focuses on the growth, adhesion, and detachment phenomena of ice by liquid jets on different types of surfaces (hydrophilic, hydrophobic, and superhydrophobic) immersed in a 10 wt% ethanol/water mixture. A liquid jet is used to detach the ice layer from the surfaces, with a velocity ranging from 0 to 2.87 m s?1, and the surface temperature varies from 25 °C to approximately -9 °C. The results show that ice adheres less to hydrophilic and hydrophobic surfaces compared to superhydrophobic surfaces. The use of PTFE-treated aluminum surfaces (hydrophobic) reduces the required flow velocity to detach the ice layer by half compared to untreated aluminum surfaces (hydrophilic). An ANSYS® Fluent numerical model was developed to simulate the evolution of turbulent velocities of immersed liquid jets, and a semi-empirical model was designed to estimate the detachment forces of soft ice from hydrophilic surfaces (untreated aluminum). Two types of ice detachment from surfaces were identified: adhesive detachment and cohesive detachment.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{belhamadia_2366,

title = {Existence and uniqueness for a convective phase change model with temperature-dependent viscosity},

author = {Youssef Belhamadia and Jean Deteix and Basma Jaffal-Moutarda and Driss Yakoubi},

url = {https://www.sciencedirect.com/science/article/pii/S0022247X23005620?via%3Dihub},

year  = {2023},

date = {2023-11-01},

journal = {Journal Of Mathematical Analysis And Applications},

volume = {527},

number = {2},

pages = {127559},

abstract = {In this article, we consider a class of phase change model with temperature-dependent viscosity, convection and mixed boundary conditions on a bounded domain that reflect melting and solidification in a variety of real-world applications, such as metal casting and crystal growth. The mathematical model, which is based on the enthalpy formulation, takes into consideration the thermophysical differences between the liquid and solid states. The moving liquid-solid interface is explicitly fulfilled as the energy and momentum equations are solved over the full physical domain. Under particular assumptions, we derive various a priori estimates and prove well-posedness results. Numerical simulation of the model employed in the

paper is presented as an illustration of an example of a melting problem.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{bernard_2401,

title = {On the Homogenization of the Renewal Equation with Heterogeneous External Constraints},

author = {Etienne Bernard and Francesco Salvarani},

url = {https://link.springer.com/article/10.1007/s10440-023-00594-2},

year  = {2023},

date = {2023-10-01},

journal = {Acta Applicandae Mathematicae},

volume = {187},

number = {1},

pages = {4},

abstract = {We study the homogenization limit of the renewal equation with heterogeneous external con- straints by means of the two-scale convergence theory. We prove that the homogenized limit satisfies an equation involving non-local terms, which are the consequence of the oscillations in the birth and death terms. We have moreover shown that the numerical approximation of the homogenized equation via the two-scale limit gives an alternative way for the numerical study of the solution of the limiting problem.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{amirat_2247,

title = {Homogenization of ferrofluid flow models in porous media with Langevin magnetization law},

author = {Youcef Amirat and Kamel Hamdache},

url = {https://www.sciencedirect.com/science/article/pii/S0022247X23001324?via%3Dihub},

year  = {2023},

date = {2023-09-01},

journal = {Journal Of Mathematical Analysis And Applications},

volume = {525},

number = {1},

pages = {127129},

abstract = {The paper is concerned with the homogenization of the equations describing the flow of a ferrofluid through a heterogeneous porous medium ? in the presence of an applied magnetic field. We discuss two models where the magnetization M is parallel to the magnetic field H. In the first one M and H satisfy the relation M=?01?fH in ?, where ?0 is a positive constant and 1?f is the characteristic function of ?f (the pore space). In the second model, M and H satisfy the Langevin magnetization law M=MsL(b1|H|)|H|1?fH, where L is the Langevin function given by L(x)=1tanh?x?1x, Ms is the saturation magnetization and b1 is a positive physical constant. The velocity and the pressure satisfy the Stokes equation with a Kelvin magnetic force. We perform the homogenization of the equations of each of the two models. Using the two-scale convergence method, we rigorously derive the homogenized equation for the magnetic potential and determine the asymptotic limit of the magnetization. Then we rigorously derive a Darcy law.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{fortin_2280,

title = {High accuracy breaking point detection for stiff DDEs},

author = {André Fortin and Driss Yakoubi},

url = {https://www.sciencedirect.com/science/article/abs/pii/S0893965923000976#d1e179},

year  = {2023},

date = {2023-09-01},

journal = {Applied Mathematics Letters},

volume = {143},

pages = {108665},

abstract = {We have recently introduced a very high order Discontinuous Galerkin (DG) method for the solution of stiff ordinary differential equations (ODEs) and delay differential equations (DDEs). In this communication we focus on the detection of breaking points frequently arising in the solution of stiff DDEs. Breaking points are discontinuities appearing in the solution of DDEs and/or in some of its derivatives. Breaking points affect the efficiency of the numerical method by forcing very small time steps in their vicinity. They also locally affect the solution accuracy. We therefore introduce a very simple breaking point detection algorithm in order to further improve the efficiency our DG method.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{salvarani_2286,

title = {Homogenization of the linear Boltzmann equation with a highly oscillating scattering term in extended phase space},

author = {Francesco Salvarani and Etienne Bernard},

url = {https://doi.org/10.1016/j.aml.2023.108672},

year  = {2023},

date = {2023-09-01},

journal = {Applied Mathematics Letters},

volume = {143},

pages = {108672},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{sama_2301,

title = {Effect of temperature anisotropy on the dynamics of geodesic acoustic modes},

author = {Juvert Njeck Sama and Alessandro Biancalani and Alberto Bottino and I Chavdarovski and Daniele Del Sarto and A Ghizzo and Thomas Hayward-Schneider and Philipp Lauber and B Rettino and Francesco Vannini},

url = {https://www.cambridge.org/core/journals/journal-of-plasma-physics/article/abs/effect-of-temperature-anisotropy-on-the-dynamics-of-geodesic-acoustic-modes/B3084D49F9505CDF3AA53221EE074E46},

year  = {2023},

date = {2023-08-01},

journal = {Journal Of Plasma Physics},

volume = {89},

number = {1},

pages = {905890109},

abstract = {In this work, we revisit the linear gyro-kinetic theory of geodesic acoustic modes (GAMs) and derive a general dispersion relation for an arbitrary equilibrium distribution function of ions. A bi-Maxwellian distribution of ions is then used to study the effects of ion temperature anisotropy on GAM frequency and growth rate. We find that ion temperature anisotropy yields sensible modifications to both the GAM frequency and growth rate as both tend to increase with anisotropy and these results are strongly affected by the electron to ion temperature ratio.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{yakoubi_2302,

title = {Enhancing the viscosity-splitting method to solve the time-dependent Navier-Stokes equations},

author = {Driss Yakoubi},

url = {https://www.sciencedirect.com/science/article/abs/pii/S100757042300182X},

year  = {2023},

date = {2023-08-01},

journal = {Communications In Nonlinear Science And Numerical Simulation},

volume = {123},

pages = {107264},

abstract = {The viscosity-splitting (VS) scheme for solving the incompressible time-dependent Navier-Stokes equations consists to decouple the full problem into two easy subproblems to resolve.

This method splits the nonlinearity (convection term) and the incompressibility into two different steps. As a result, every subproblem is easier to solve than the Navier-Stokes system. The semi-implicit approach is mostly used in the first step for the nonlinearity term and the intermediate velocity is calculated by dropping the pressure gradient. We then resolve a linear Stokes problem in the next step.

We present a modified viscosity-splitting scheme (Incremental viscosity-splitting) (IVS) to improve this method. This scheme adds the gradient of the pressure (calculated at the previous time step) in the first step and modifies the Stokes equations in the second step to

predict a better value of the intermediate velocity. A manufactured solution and two well-known benchmarks will be used to demonstrate the effectiveness of the suggested strategy.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{charles_2316,

title = {Mathematical and numerical study of a kinetic model describing the evolution of planetary rings},

author = {Frédérique Charles and Annamaria Massimini and Francesco Salvarani},

url = {https://www.sciencedirect.com/science/article/pii/S0898122123001724},

year  = {2023},

date = {2023-08-01},

journal = {Computers & Mathematics With Applications},

volume = {143},

pages = {48-56},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{salehy_2291,

title = {Rheological properties of CO2 hydrate slurries in presence of Dioctyl sodium sulfosuccinate (AOT) in a dynamic loop for refrigeration application},

author = {Yasmine Salehy and Pascal Clain and Amokrane Boufares and Nada Chami and Jean-Philippe Torré and Didier Dalmazzone and Laurence Fournaison and Anthony Delahaye},

url = {https://www.sciencedirect.com/science/article/pii/S0009250923002725?via%3Dihub},

year  = {2023},

date = {2023-07-01},

journal = {Chemical Engineering Science},

volume = {275},

pages = {118716},

abstract = {Recent studies have shown real potential for using hydrate slurries as a secondary fluid in indirect refrigeration systems. However, pipeline clogging problems can appear due to hydrate agglomeration. Additives are generally used to counteract these problems. In this study, rheological properties of CO2 hydrate slurries in the presence of an additive Dioctyl sodium sulfosuccinate (AOT) are investigated. The capillary viscometer method is used to determine the fluid behaviour and the AOT impact on the slurry rheology. A dynamic loop is set up to collect experimental pressure drop and volume flow rate data. Based on the Rabinowitch and Mooney approach and Herschel-Bulkley model to determine the rheological properties, a shear-thinning behaviour was observed. The importance of the behaviour index choice in the procedure is discussed. Finally, the results obtained with AOT are compared with pre-existing studies. The present study highlights the AOT potential to significantly improve the CO2 hydrate slurries properties.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{shirinbayani_2367,

title = {Manufacturing Process Effect on the Mechanical Properties of Glass Fiber/Polypropylene Composite Under High Strain Rate Loading: Woven (W?GF?PP) and Compressed GF50?PP},

author = {Mohammadali Shirinbayani and Abbasnezhad Navideh and Mohammad Hossein Nikooharf and Khaled Benfriha and Achraf Kallel and Jendli Zouhaier and Joseph Fitoussi},

url = {https://link.springer.com/article/10.1007/s10443-023-10143-7},

year  = {2023},

date = {2023-07-01},

journal = {Applied Composite Materials},

abstract = {Long glass fiber thermoplastic laminates have garnered significant attention for their potential use in designing structural parts across various sectors, including automotive, aerospace, and petroleum. The growing demand for lightweight and reliable materials in hydrogen vessel reservoirs, intended for future vehicles, necessitates understanding the fast dynamic behavior (crash) of these materials for effective structural design in such applications.

This study presents an optimized approach for experimentally characterizing the overall dynamic mechanical behavior of Twill woven glass fiber reinforced polypropylene (W-GF-PP) laminates. The methodology focuses on reporting the strain rate effect on the

material response while attempting to isolate the inherent inertial disturbances in the specimen attributed to the test system. Tensile tests have been conducted until the specimen's total failure for three specific relative orientations of fiber: 0°, 90°, and ± 45°. The tests

span a strain rate range from quasi-static (10-4 s?1) up to 2000 mm?s?1 (approximately 160 s?1, depending on the specimen's actual response). The material's behavior appears sensitive, particularly for the ± 45° fiber orientation. The study also examines the impact of

the manufacturing process type on the dynamic behavior of the reinforced polypropylene.},

keywords = {},

pubstate = {online},

tppubtype = {article}

}

@article{talhouk_2369,

title = {On well-posedness for some Korteweg-de Vries type equations with variable coefficients},

author = {Raafat Talhouk and Luc Molinet and Ibtissame Zaiter},

url = {https://doi.org/10.1007/s00028-023-00904-z},

year  = {2023},

date = {2023-07-01},

journal = {Journal Of Evolution Equations},

volume = {23},

number = {3},

pages = {52},

abstract = {In this paper, KdV-type equations with time- and space-dependent coefficients are considered. Assuming that the dispersion coefficient in front of uxxx is positive and uniformly bounded away from zero and that a primitive function of the ratio between the anti-dissipation and the dispersion coefficients is bounded from below, we prove the existence and uniqueness of a solution u such that hu belongs to a classical Sobolev space, where h is a function related to this ratio. The LWP in Hs(R), s > 1/2, in the classical (Hadamard) sense is also proven under this time an assumption of boundedness of the above primitive function. Our approach combines a change of unknown with dispersive estimates. Note that previous results were restricted to Hs(R), s > 3/2, and only used the dispersion to compensate the anti-dissipation and not to lower the Sobolev index required for well-posedness.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{khadimallah_2380,

title = {Characterization of fatigue behavior of AA2024-T351 aluminum alloy},

author = {Aymen Khadimallah and Johann Petit and Naila Hfaiedh and Amna Znaidi},

url = {https://onlinelibrary.wiley.com/share/author/5HS4PJKGQVKNQNGDT9QT?target=10.1111/ffe.14102},

year  = {2023},

date = {2023-07-01},

journal = {Fatigue & Fracture Of Engineering Materials & Structures},

abstract = {The paper aims to investigate the fatigue behavior of the widely used

AA2024-T351 aluminum alloy in the aircraft industry. An experimental program

was conducted to study the fatigue life and damage behavior under symmetrical

tensile-compressive loading. Cyclic tests in the low cycle fatigue

regime were performed under fully reversed total strain amplitudes from 0.6%

to 1.2%. The AA2024-T351 alloy exhibited cyclic hardening until failure. Symmetric

high cycle fatigue tests were also performed and the parameters for

fatigue life estimation using the Manson-Coffin-Basquin model were identified.

Elasto-plastic behavior was analyzed through stress-strain hysteresis

loops, evaluating kinematic and isotropic hardenings. Kinematic hardening

was found to be strain amplitude dependent, unlike the isotropic hardening.

The evolution of the isotropic variable with the percentage of fatigue life could

be described by an exponential law. Fractography investigations showed crack

initiation at the specimen border with quasi-cleavage and then crack propagating

by striation before ductile fracture.},

keywords = {},

pubstate = {online},

tppubtype = {article}

}

@article{daikh_2353,

title = {Augmented spectral formulation for the Stokes problem with variable viscosity and mixed boundary conditions},

author = {Yasmina Daikh and Sarra Maarouf and Driss Yakoubi and Chaima Bousbia},

url = {https://link.springer.com/article/10.1007/s10092-023-00530-8},

year  = {2023},

date = {2023-06-01},

journal = {Calcolo},

volume = {60},

number = {3},

pages = {2-23},

abstract = {This paper deals with the analysis of a new augmented formulation in terms of vorticity, velocity and pressure for the Stokes equations with variable viscosity and mixed boundary conditions. The well-posedness of the continuous problem holds under assumptions on the viscosity. When the domain is a parallelepiped, the spectral discretization is proposed using the Galerkin method with numerical integration. Then, we prove the well-posedness of the obtained discrete problem under the same type of conditions on the viscosity. A priori error estimates is then derived for the three

unknowns. Finally, numerical experiments are presented that confirm the interest of

the discretization.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{hamdache_2246,

title = {The Bloch-Torrey limit of a kinetic transport system},

author = {Kamel Hamdache and Djamila Hamroun},

url = {https://link.springer.com/article/10.1007/s00009-023-02328-y#citeas},

year  = {2023},

date = {2023-06-01},

journal = {Mediterranean Journal Of Mathematics},

volume = {20},

number = {3},

pages = {122},

abstract = {This work is devoted to highlighting the diffusion of some models of Kinetic-Bloch system by an asymptotic analysis. The limit of the kinetic equation when using the classical diffusion scaling shows that the magnetization field becomes parallel to the magnetic field. For the limit of the magnetization when we use a second scaling of the kinetic equation, we show that the dynamics of the magnetization is driven by the Bloch-Torrey diffusion equation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{bousbia_2353,

title = {Augmented spectral formulation for the Stokes problem with variable viscosity and mixed boundary conditions},

author = {Chaima Bousbia and Yasmina Daikh and Sarra Maarouf and Driss Yakoubi},

url = {https://link.springer.com/article/10.1007/s10092-023-00530-8},

year  = {2023},

date = {2023-06-01},

journal = {Calcolo},

volume = {60},

number = {3},

pages = {36},

abstract = {This paper deals with the analysis of a new augmented formulation in terms of vorticity, velocity and pressure for the Stokes equations with variable viscosity and mixed boundary conditions. The well-posedness of the continuous problem holds under assumptions on the viscosity. When the domain is a parallelepiped, the spectral discretization is proposed using the Galerkin method with numerical integration. Then, we prove the well-posedness of the obtained discrete problem under the same type of conditions on the viscosity. A priori error estimates is then derived for the three

unknowns. Finally, numerical experiments are presented that confirm the interest of

the discretization.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{bader_1995,

title = {Microscopic tridomain model of electrical activity in the heart with dynamical gap junctions. Part 2 - Derivation of the macroscopic tridomain model by unfolding homogenization method},

author = {Fakhrielddine Bader and Mostafa Bendahmane and Mazen Saad and Raafat Talhouk},

url = {https://doi.org/10.3233/ASY-221804},

year  = {2023},

date = {2023-05-01},

journal = {Asymptotic Analysis},

volume = {132},

number = {3-4},

pages = {575-606},

abstract = {We study the homogenization of a novel microscopic tridomain system, allowing

for a more detailed analysis of the properties of cardiac conduction than the classical bidomain

and monodomain models. In [5], we detail this model in which gap junctions are considered

as the connections between adjacent cells in cardiac muscle and could serve as alternative

or supporting pathways for cell-to-cell electrical signal propagation. Departing from this mi-

croscopic cellular model, we apply the periodic unfolding method to derive the macroscopic

tridomain model. Several diculties prevent the application of unfolding homogenization

results, including the degenerate temporal structure of the tridomain equations and a nonlin-

ear dynamic boundary condition on the cellular membrane. To prove the convergence of the

nonlinear terms, especially those dened on the microscopic interface, we use the boundary

unfolding operator and a Kolmogorov-Riesz compactness's result.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{fortin_2076,

title = {A very high order discontinuous Galerkin method for the numerical solution of stiff DDEs},

author = {André Fortin and Driss Yakoubi},

url = {https://www.sciencedirect.com/science/article/pii/S0096300322008359},

year  = {2023},

date = {2023-04-01},

journal = {Applied Mathematics And Computation},

volume = {443},

pages = {127767},

abstract = {We present a high order discontinuous Galerkin (DG) method for the numerical solution of systems of delay differential equations (DDEs). The method is based on Legendre orthogonal polynomials of high degree k (typically k=10) in each subinterval and is a generalisation to DDEs of a similar method which proved to be very efficient for ordinary differential equations (ODEs). We show how the error can be estimated allowing to control the size of the time step. We also propose a particularly efficient quasi Newton method for the solution of the resulting non linear systems based on a very accurate approximation of the Jacobian matrix that is very easy to implement and with excellent convergence properties. The method is then applied to very stiff systems of DDEs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{boussoufa_2305,

title = {Numerical analysis for backward Euler spectral discretization for Stokes equations with boundary conditions involving the pressure: part I},

author = {Oussama Boussoufa and Yasmina Daikh and Driss Yakoubi},

url = {https://link.springer.com/article/10.1007/s10092-023-00520-w},

year  = {2023},

date = {2023-04-01},

journal = {Calcolo},

volume = {60},

number = {2},

pages = {1--27},

abstract = {In this paper, we address the study of the time-dependent Stokes system with boundary conditions involving the pressure. We obtain existence and uniqueness for a classof Lipschitz-continuous domains. Next, a spectral discretizations of the problem is

proposed combined with the backward Euler scheme. The discrete spaces are defined in a way to give exactly divergence-free discrete approximations for the velocity. Then, we prove the associated discrete inf-sup condition and derive a priori error estimates.

Finally, some numerical experiments are presented},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{schittecatte_2327,

title = {From resin formulation and process parameters to the final mechanical properties of 3D printed acrylate materials},

author = {Laura Schittecatte and Valérie Geertsen and Daniel Bonamy and Thuy Nguyen and Patrick Guenoun},

url = {https://link.springer.com/article/10.1557/s43579-023-00352-3},

year  = {2023},

date = {2023-04-01},

journal = {Mrs Communications},

volume = {13},

pages = {357-377},

abstract = {Photopolymerizable resins are increasingly used to generate complex 3D printed parts through stereo lithography, digital light processing (DLP) and

liquid crystal display (LCD) 3D printing. Many challenges relating to the resin chemistry and printing parameters still exist and must be addressed in order to entirely control the properties of parts after printing. This work reviews the current knowledge and describes the potential of DLP/LCD methods for printed acrylate resins, as well as the steps necessary to achieve a better control over the mechanical properties of printed materials.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{mishchenko_2378,

title = {Numerical tools for burning plasmas},

author = {Alexey Mishchenko and Alessandro Biancalani and Juvert Njeck Sama and Alberto Bottino and Sergio Briguglio and M Borchardt and Emanuele Poli and Remi Dumont and Jorge Ferreira and J P Graves and Ralf Kleiber and B Rettino and Thomas Hayward-Schneider and Axel Koenies and Emmanuel Lanti and Philipp Lauber and H Leyh and Zhixin Lu and Hinrich Luetjens and Ben McMillan and Martin Campos Pinto and Baruch Rofman and Christoph Slaby and Francesco Vannini and Laurent Villard and Gregorio Vlad and Xin Wang and Fabien Widmer and Fulvio Zonca},

url = {https://iopscience.iop.org/article/10.1088/1361-6587/acce68},

year  = {2023},

date = {2023-04-01},

journal = {Plasma Physics And Controlled Fusion},

volume = {65},

number = {6},

pages = {064001},

abstract = {The software stack under development within a European coordinated effort on tools for burning plasma modelling is presented. The project is organised as a Task (TSVV Task 10) under the new E-TASC initiative (Litaudon et al 2022 Plasma Phys. Control. Fusion64 034005). This is a continued effort within the EUROfusion inheriting from the earlier European coordination projects as well as research projects based at various European laboratories. The ongoing work of the TSVV Tasks is supported by the Advanced Computing Hubs. Major projects requiring the high performance computing (HPC) resources are global gyrokinetic codes and global hybrid particle-magnetohydrodynamics (MHD) codes. Also applications using the integrated modelling tools, such as the Energetic-Particle Workflow, based on the ITER Integrated Modelling & Analysis Suite (IMAS), or the code package for modelling radio-frequency heating and fast-ion generation may require intensive computation and a substantial memory footprint. The continual development of these codes both on the physics side and on the HPC side allows us to tackle frontier problems, such as the interaction of turbulence with MHD-type modes in the presence of fast particles. One of the important mandated outcomes of the E-TASC project is the IMAS-enabling of EUROfusion codes and release of the software stack to the EUROfusion community.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{biancalani_2301,

title = {Effect of temperature anisotropy on the dynamics of geodesic acoustic modes},

author = {Alessandro Biancalani and Alberto Bottino and I Chavdarovski and A Ghizzo and Thomas Hayward-Schneider and Philipp Lauber and B Rettino and Francesco Vannini},

url = {https://www.cambridge.org/core/article/effect-of-temperature-anisotropy-on-the-dynamics-of-geodesic-acoustic-modes/B3084D49F9505CDF3AA53221EE074E46},

year  = {2023},

date = {2023-03-01},

journal = {Journal Of Plasma Physics},

volume = {89},

number = {1},

pages = {905890109},

abstract = {In this work, we revisit the linear gyro-kinetic theory of geodesic acoustic modes (GAMs) and derive a general dispersion relation for an arbitrary equilibrium distribution function of ions. A bi-Maxwellian distribution of ions is then used to study the effects of ion temperature anisotropy on GAM frequency and growth rate. We find that ion temperature anisotropy yields sensible modifications to both the GAM frequency and growth rate as both tend to increase with anisotropy and these results are strongly affected by the electron to ion temperature ratio.},

keywords = {},

pubstate = {accepted},

tppubtype = {article}

}

@article{samah_2080,

title = {Review on ice crystallization and adhesion to optimize ice slurry generators without moving components},

author = {Walid Samah and Pascal Clain and François Rioual and Laurence Fournaison and Anthony Delahaye},

url = {https://www-sciencedirect-com.devinci.idm.oclc.org/science/article/pii/S1359431123000030},

year  = {2023},

date = {2023-03-01},

journal = {Applied Thermal Engineering},

volume = {223},

pages = {119974},

abstract = {The current climate crisis requires a radical reduction in energy consumption and greenhouse gas emissions. For the refrigeration industry, secondary refrigeration is one of the most accessible solutions to reduce the use of refrigerants with high greenhouse gas content. In addition, the use of low environmental impact two-phase secondary fluids, namely PCM (phase change material) slurries, such as ice slurries and gas hydrate slurries, can limit the electrical energy consumption involved in the process. Currently, the industry's most commonly used ice slurry production systems are scraped surface and supercooling generators. These have some disadvantages, such as maintenance costs and energy consumption. An ice slurry generator is considered efficient if it meets three criteria: continuous production, low energy consumption and reliable operation. Optimizing ice slurry production with generators without moving components (scraped surface) could be a solution to meet these criteria. The objective of this review is to present a critical analysis of ice slurry production optimization methods proposed in the literature. These methods aim either to prevent ice nucleation to produce supercooled water with a high supercooling degree, or to reduce the adhesion of the ice to the generator walls to facilitate its removal by flow or by external forces (gravity and buoyancy).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{venkateswaran_2256,

title = {Mapping the Tilt & Torsion angles for a 3-SPS-U parallel mechanism},

author = {Swaminath Venkateswaran and Damien Charles Chablat},

url = {https://www.mdpi.com/2218-6581/12/2/50},

year  = {2023},

date = {2023-03-01},

journal = {Robotics},

volume = {12},

number = {2},

pages = {50},

abstract = {This article presents the analysis of a parallel mechanism of type 3-SPS-U. The usual singularity approach is carried out with respect to the Euler angles of the universal joint. However, this approach is computationally expensive especially when stacked structures are analyzed. Thus, the positioning of the mobile platform for the mechanism is analyzed using the theory of Tilt & Torsion (T&T). The singularity-free workspace and the tilt limits of the mechanism are disclosed through this method. These workspaces can then be mapped to the Euler angles of the universal joint and the relation between the T & T space and the Euler space is demonstrated and validated in this study. Initially, simulations are performed using the results of singularity analysis to have a comparison between the T&T space and the Euler space. Experimental validation is then carried out on the prototype of the mechanism to perform a circular trajectory, in line with the simulations. The outcome of this study will be helpful for the integration of the mechanism for a piping inspection robot and also for the analysis of stacked architectures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{borsoni_1875,

title = {Compactness property of the linearized Boltzmann operator for a polyatomic gas undergoing resonant collisions},

author = {Thomas Borsoni and Laurent Boudin and Francesco Salvarani},

url = {https://www.sciencedirect.com/science/article/pii/S0022247X22005935?via%3Dihub},

year  = {2023},

date = {2023-01-01},

journal = {Journal Of Mathematical Analysis And Applications},

volume = {517},

number = {1},

pages = {126579},

abstract = {In this paper, we investigate a compactness property of the linearized Boltzmann operator in the context of a polyatomic gas whose molecules undergo resonant collisions. The peculiar structure of resonant collision rules allows to tensorize the problem into a velocity-related one, neighbouring the monatomic case, and an internal energy-related one. Our analysis is based on a specific treatment of the internal energy contributions. We also propose a geometric variant of Grad's proof of the same compactness property in the monatomic case.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{chami_1961,

title = {Rheological study of mixed cyclopentane + CO2 hydrate slurry in a dynamic loop for refrigeration systems},

author = {Nada Chami and Yasmine Salehy and Dennis Burgner and Pascal Clain and Didier Dalmazzone and Anthony Delahaye and Laurence Fournaison},

url = {https://www.sciencedirect.com/science/article/pii/S0360544222025476},

year  = {2023},

date = {2023-01-01},

journal = {Energy},

volume = {263},

pages = {125661},

abstract = {The use of CO2 hydrates as phase change materials is promising for secondary loop refrigeration, as these compounds present adjustable dissociation temperature that can be higher than 273.15 K and have high enthalpy of dissociation. In the present work, by using various promoters, cyclopentane (CP) in this study, the formation pressure of hydrates may be significantly lowered than CO2 hydrates. For their application as a secondary refrigerant, the rheological properties of mixed CP + CO2 hydrate slurry need to be controlled. The flow properties of CP and mixed CP + CO2 hydrate slurries were studied in a dynamic flow loop at different cyclopentane contents ranging from 3 wt% to 15 wt%, using a capillary viscometer based on Rabinowitch and Mooney equation. Rheological parameters (viscosity, flow behavior...) related to these two slurries were compared. The experimental results demonstrate that CP and mixed CP + CO2 hydrates slurries exhibit a shear thinning behavior and the viscosity values vary between 3 and 12 mPa.s-1 at [100-1000 s?1] for CP hydrates slurries and between 2 and 10 mPa s?1 at [100-1200 s?1] for CP + CO2 hydrates slurries. CP hydrate and CP + CO2 hydrate slurry viscosity is close to that of TBPB hydrate and lower than that of CO2 hydrate. Moreover, mixed CP + CO2 have shown a time-evolution of the rheological behavior.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{samah_2025,

title = {Experimental investigation on the wetting behavior of a superhydrophobic surface under controlled temperature and humidity},

author = {Walid Samah and Pascal Clain and François Rioual and Laurence Fournaison and Anthony Delahaye},

url = {https://www.sciencedirect.com/science/article/pii/S0927775722022063},

year  = {2023},

date = {2023-01-01},

journal = {Colloids And Surfaces A-Physicochemical And Engineering Aspects},

volume = {656},

pages = {130451},

abstract = {Superhydrophobic surfaces (SHS) are of great interest in various industrial fields. However, the application of these surfaces in cold, humid and submerged environments (as in the case of ice slurry production) sometimes presents problems related to the loss of their superhydrophobic properties. This paper presents an experimental study in order to characterize the wetting behavior of a surface coated with a commercial superhydrophobic "Ultra Ever Dry" (UED) coating at different surface temperatures (from 22 °C to ? 13 °C) and relative humidity (13%, 20%, 30%, 40% and 50%). Three methods are developed to characterize the wetting behavior. The first method consists in depositing a water drop on the cooled superhydrophobic UED surface. The objective is to characterize the static wetting behavior (evolution of contact angles) during the cooling of the surface for different relative humidity. The second method consists in dropping a water drop on the cooled UED superhydrophobic surface with an impact velocity of 1 m s?1. This method allows the dynamic behavior of the wetting (impact and rebound of the drop) to be characterized at different temperatures. The third method, consists in studying the effect of the immersion of the SHS in a volume of water cooled until supercooling then freezing. The aim is to analyze the wetting behavior in immersion at low temperature. The results of the static wetting study show that the superhydrophobic coating loses its non-wetting properties at temperatures below 13 °C for a relative humidity between 13% and 50% due to condensation on the surface. The results of the dynamic wetting study show that the superhydrophobic coating has poor resistance to water drop impact at surface temperatures below 4 °C. The wetting transition from Cassie to Wenzel state in low temperature immersion is caused by ice formation. The wettability state influences the morphology of the ice produced after freezing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@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}

}