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Piezoelectric resonant ice protection systems–Part1/2:Prediction of power requirement for de-icing a NACA 0024 leading edge

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Chinese Journal of Aeronautics 2024年第3期37卷 92-103页

作者： Valerian PALANQUE Jason POTHIN Vale′rie POMMIER-BUDINGER Marc BUDINGER Institut Clement Ader University of ToulouseINSAISAE-SUPAEROMINES ALBIUPSCNRSToulouse 31055France ISAE-SUPAERO University of Toulouse10 Avenue Edouard BelinToulouse 31055France

This paper proposes a numerical method to analyze the ice protection capability and predict the power requirements of a piezoelectric resonant de-icing *** method is based on a coupled electro-mechanical finite element analysis which enables the fast computation of the modes of resonance of interest to de-ice curved surfaces and the estimation of the input voltage and current required for a given configuration(defined by its mode,actuator location,ice deposit,etc.).Eventually,the electric power to be supplied can be also *** method is applied to a NACA 0024 leading edge equipped with piezoelectric ***,two extension modes are analyzed and compared with respect to their efficiency and power ***,tests are carried out in an icing tunnel to verify the effectiveness of the piezoelectric ice protection system and the predictions of the maximal required *** system allows de-icing the leading edge in less than 2 s for a glaze ice deposit.

关键词： Ice protection system Piezoelectric Resonance mode Ice fracture Leading edge de-icing

Piezoelectric resonant ice protection systems-Part 2/2:Evaluation of benefits at aircraft level

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Chinese Journal of Aeronautics 2024年第6期37卷 50-63页

作者： Valerian PALANQUE Thomas PLANES Pommier-Budinger VALERIE Budinger MARC Delbecq SCOTT Institut Clement Ader(ICA) INSAISAE-SUPAEROMINES ALBIUPSCNRSUniversity of Toulouse31400 ToulouseFrance Federation ENAC ISAE-SUPAERO ONERA University of Toulouse31400 ToulouseFrance

Piezoelectric resonant de-icing systems are attracting great *** paper aims to assess the implementation of these systems at the aircraft *** article begins with the model to compute the power requirement of a piezoelectric resonant de-icing system sized from the prototype detailed in Part 1/2 of this *** the mass,drag,and fuel consumption of this system and the subcomponents needed for its implementation are *** features of a piezoelectric resonant de-icing system are finally computed for aircraft similar to Airbus A320 aircraft and aircraft of different categories(Boeing 787,ATR 72 and TBM 900)and compared with the existing thermal and mechanical ice protection systems.A sensitivity analysis of the main key sizing parameters of the piezoelectric de-icing system is also performed to identify the main axes of improvement for this *** study shows the potential of such ice protection *** particular,for the realistic input parameters chosen in this work,the electro-mechanical solution can provide a 54% reduction in terms of mass and a 92% reduction in terms of power consumption for an A320 aircraft architecture,leading to a 74% decrease in the associated fuel consumption compared to the actual air bleed system.

关键词： Ice protection system De-icing Piezoelectric Electro-mechanical system Power Fuel consumption

Optical probing of ultrafast laser-induced solid-to-overdense-plasma transitions

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Light(Science & Applications) 2024年第5期13卷 973-984页

作者： Yasmina Azamoum Georg Alexander Becker Sebastian Keppler Guillaume Duchateau Stefan Skupin Mickael Grech Fabrice Catoire Sebastian Hell Issa Tamer Marco Hornung Marco Hellwing Alexander Kessler Franck Schorcht Malte Christoph Kaluza GSI Helmholtzzentrum für Schwerionenforschung Planckstr.164291 DarmstadtGermany. Helmholtz Institute Jena Fröbelstieg 307743 JenaGermany. Institute of Optics and Quantum Electronics Friedrich-SchillerUniversität JenaMax-Wien-Platz 107743 JenaGermany. CEA-CESTA 15 Avenue des SablièresCS6000133116 Le BarpCedexFrance Institut Lumière Matière UMR 5306-CNRSUniversitéde Lyon 169622 VilleurbanneFrance. LULI CNRSCEASorbonne UniversitéInstitut Polytechnique de ParisPalaiseauFrance. Universitéde Bordeaux-cnrs-CEA CELIAUMR 5107 TalenceFrance

Understanding the solid target dynamics resulting from the interaction with an ultrashort laser pulse is a challenging fundamental multi-physics problem involving atomic and solid-state physics,plasma physics,and laser *** of the initial interplay of the underlying processes is essential to many applications ranging from lowpower laser regimes like laser-induced ablation to high-power laser regimes like laser-driven ion *** the properties of the so-called pre-plasma formed as the laser pulse’s rising edge ionizes the target is complicated from the theoretical and experimental point of view,and many aspects of this laser-induced transition from solid to overdense plasma over picosecond timescales are still open *** the one hand,laser-driven ion acceleration requires precise control of the pre-plasma because the efficiency of the acceleration process crucially depends on the target properties at the arrival of the relativistic intensity peak of the *** the other hand,efficient laser ablation requires,for example,preventing the so-called“plasma shielding”.By capturing the dynamics of the initial stage of the interaction,we report on a detailed visualization of the pre-plasma formation and ***-thin diamond-like carbon foils are shown to transition from solid to plasma during the laser rising edge with intensities<10^(16)W/cm^(2).Single-shot near-infrared probe transmission measurements evidence sub-picosecond dynamics of an expanding plasma with densities above 10^(23)cm^(−3)(about 100 times the critical plasma density).The complementarity of a solid-state interaction model and kinetic plasma description provides deep insight into the interplay of initial ionization,collisions,and expansion.

关键词： laser acceleration solid

Numerical study on waste polyethylene pyrolysis driven by self-sustaining smoldering

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Science China(Technological Sciences) 2024年第2期67卷 627-638页

作者： PAN RuMing WU YiBo GUENE LOUGOU Bachirou SHUAI Yong DEBENEST Gérald School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Institut de Mecanique des Fluides de Toulouse(IMFT)-Universite de Toulouse CNRS-INPT-UPSToulouse 31400France

Polyethylene is the type of waste plastic that accounts for the most significant proportion of municipal solid *** polyethylene can be valorized via pyrolysis and produce value-added oil,gas,and *** the other hand,self-sustaining smoldering is an emerging technical means to deal with sand/soil contaminated by organic *** high-temperature heat generated by smoldering can be used as a heat source for pyrolyzing waste ***,this study investigates numerically the pyrolysis of waste polyethylene driven by self-sustaining smoldering.A novel 4-step lumped kinetic model is proposed for simulating the pyrolysis of waste *** results indicate that the operating parameters can determine the pyrolysis product yields by regulating the pyrolysis temperature and the volatile residence *** that higher temperatures and longer residence times favor the generation of shorter-chain pyrolysis products because of the intensified volatiles’secondary *** can be concluded that a high interface-wall heat transfer coefficient(400 W m^(-2)K^(-1)),a low PE content(0.20),a high char concentration(2.4%),and a moderate air velocity(0.040 m s^(-1))are beneficial to oil *** some extent,this study may broaden the boundaries for the application of self-sustained smoldering-driven pyrolysis.

关键词： self-sustained smoldering waste polyethylene thermal decomposition oil production waste valorization

Probabilistic Global Maximum Power Point Tracking Algorithm for Continuously Varying Partial Shading Conditions on Autonomous PV Systems

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Energy and Power Engineering 2024年第1期16卷 21-42页

作者： Kha Bao Khanh Cao Vincent Boitier LAAS-cnrs University of Toulouse Toulouse France

A photovoltaic (PV) string with multiple modules with bypass diodes frequently deployed on a variety of autonomous PV systems may present multiple power peaks under uneven shading. For optimal solar harvesting, there is a need for a control schema to force the PV string to operate at global maximum power point (GMPP). While a lot of tracking methods have been proposed in the literature, they are usually complex and do not fully take advantage of the available characteristics of the PV array. This work highlights how the voltage at operating point and the forward voltage of the bypass diode are considered to design a global maximum power point tracking (GMPPT) algorithm with a very limited global search phase called Fast GMPPT. This algorithm successfully tracks GMPP between 94% and 98% of the time under a theoretical evaluation. It is then compared against Perturb and Observe, Deterministic Particle Swarm Optimization, and Grey Wolf Optimization under a sequence of irradiance steps as well as a power-over-voltage characteristics profile that mimics the electrical characteristics of a PV string under varying partial shading conditions. Overall, the simulation with the sequence of irradiance steps shows that while Fast GMPPT does not have the best convergence time, it has an excellent convergence rate as well as causes the least amount of power loss during the global search phase. Experimental test under varying partial shading conditions shows that while the GMPPT proposal is simple and lightweight, it is very performant under a wide range of dynamically varying partial shading conditions and boasts the best energy efficiency (94.74%) out of the 4 tested algorithms.

关键词： Photovoltaic PV Global Maximum Power Point Tracking GMPPT Fast Varying Partial Shading Conditions Autonomous PV Systems GMPPT Review

Effects of Andrade and Burgers rheologies on glacial isostatic adjustment modeling in Antarctica

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Geodesy and Geodynamics 2024年第5期15卷 429-440页

作者： Alexandre Boughanemi Anthony Mémin UniversitéCôte d'Azur CNRSObservatoire de la Côte d'AzurIRDGéoazur250 rue Albert EinsteinSophia Antipolis 06560 ValbonneFrance

Variations in ice mass deform the Earth and modify its gravity field,a process known as Glacial Isostatic Adjustment(GIA).GIA in Antarctica remains poorly constrained due to the cumulative effect of past and present ice-mass changes,the unknown history of the past ice-mass change,and the uncertainties on the mechanical properties of the *** paper investigates the effect of using Andrade and Burgers viscoelastic rheologies,rather than the commonly used Maxwell rheology,to model GIA-induced deformation in *** Love number and Green's function formalism are used to compute the radial surface displacements and the gravity changes induced by the past and present ice-mass *** consider an Earth model whose elastic properties and radial structure are averaged from the Preliminary Reference Earth Model and two viscosity profiles to account for the recently published results on the present ice-mass *** the three rheological laws affects the temporal response of the Earth differently,leading to smaller discrepancies than those induced by the two viscosity *** differences are the largest between Maxwell and Burgers rheologies during the 100-1000 years following the beginning of the surface-mass *** show that using the Andrade and Burgers rheologies allows the Earth to respond on decennial to centennial time scales,up to 10 m more than *** only the recent ice-mass changes,the deformation rates derived from Burgers and Andrade rheologies are several times larger than those estimated by Maxwell rheology.

关键词： GIA Antarctica Modeling Rheology Displacement Viscosity GNSS

Bound and Resonating Multiquark Configurations

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Chinese Physics Letters 2024年第8期41卷 8-12页

作者： Jean-Marc Richard Institut de Physique des 2 Infinis de Lyon Université Claude Bernard(Lyon 1) CNRS-IN2P34 rue Enrico Fermi69622 VilleurbanneFrance

We review the predictions of quark models for multiquark configurations that are bound or resonant states,and compare different methods for estimating the properties of resonances.

关键词： quark Configuration resonant

Diatom and Diatomite: Different Focus on Natural Media to Material Science Path

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American Journal of Analytical Chemistry 2024年第1期15卷 1-29页

作者： Secou Sall Vasiliki Papaefthimiou Thierry Dintzer Fabrice Vigneron Eric Brendlé Pierre Petit Tom Ferte Saliha Haddoum Sana Labidi Corinne Petit ICPEES UMR-CNRS 7515 Strasbourg University Strasbourg France Adscientis Wittelsheim France ICS CNRS UPR 22 Strasbourg France IPCMS UMR CNRS 7504 Strasbourg University Strasbourg France Ecole Nationale Polytechnique El-Harrach Algeria

Bio-silica issued from diatom, a microalgae, is attracted increasing attention in material science thanks to its peculiar nanoarchitecture and related properties with versatile applications. The present work is a deep analysis on morphological and chemical properties of bio-silica issued from fossil origin (diatomaceous earth) and living one (algal paste). An optimization in purification protocol was performed to obtain multiparous bio-silica from its raw media with keeping its original shape entirely. Multiple characterization methods as scanning electronic microscopy (SEM), infrared spectroscopy, x-ray diffraction (DRX), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), nitrogen adsorption and inverse gas chromatography (IGC), were used to check the purification protocol efficiency as well as to gather accurate information on morphology and chemical composition of diatom material obtained in large amount.

关键词： Diatom Diatomite Bio-Silica Purification Frustule

A level line of the Gaussian free field with measure-valued boundary conditions

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Science China Mathematics 2024年第2期67卷 367-404页

作者： Titus Lupu Hao Wu Laboratoire de Probabilités Statistique et ModélisationSorbonne Universitéand UniversitéParis CitéCNRSParis F-75005France Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China

In this article, we construct samples of Schramm-Loewner-evolution-like curves out of samples ofthe conformal loop ensemble and Poisson point processes of Brownian excursions. We show that the laws of thesecurves depend continuously on the intensity measure of the Brownian excursions. Using such a construction ofcurves, we extend the notion of level lines of the Gaussian free field to the case where the boundary conditionis measure-valued.

关键词： Schramm-Loewner evolution conformal loop ensemble Brownian excursion Gaussian free field