Готові списки джерел за темами / Quasi-ALE

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Добірка наукової літератури з теми "Quasi-ALE"

Автор: Grafiati

Опубліковано: 12 жовтня 2024

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Статті в журналах з теми "Quasi-ALE"

Ma, Q. W., and S. Yan. "Quasi ALE finite element method for nonlinear water waves." Journal of Computational Physics 212, no. 1 (February 2006): 52–72. http://dx.doi.org/10.1016/j.jcp.2005.06.014.

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Lee, Hyesuk. "Numerical approximation of Quasi-Newtonian flows by ALE-FEM." Numerical Methods for Partial Differential Equations 28, no. 5 (August 25, 2011): 1667–95. http://dx.doi.org/10.1002/num.20698.

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Boman, R., and J. P. Ponthot. "Efficient ALE mesh management for 3D quasi-Eulerian problems." International Journal for Numerical Methods in Engineering 92, no. 10 (June 6, 2012): 857–90. http://dx.doi.org/10.1002/nme.4361.

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Honda, M., T. Katsunuma, M. Tabata, A. Tsuji, T. Oishi, T. Hisamatsu, S. Ogawa, and Y. Kihara. "Benefits of atomic-level processing by quasi-ALE and ALD technique." Journal of Physics D: Applied Physics 50, no. 23 (May 16, 2017): 234002. http://dx.doi.org/10.1088/1361-6463/aa6f27.

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Honda, M., T. Katsunuma, M. Tabata, A. Tsuji, T. Oishi, T. Hisamatsu, S. Ogawa, and Y. Kihara. "(Invited) Plasma-Enhanced Quasi-ALE and ALD Processing for Leading-Edge Microfabrication." ECS Transactions 75, no. 6 (September 23, 2016): 3–10. http://dx.doi.org/10.1149/07506.0003ecst.

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Stupkiewicz, Stanisław. "An ALE formulation for implicit time integration of quasi-steady-state wear problems." Computer Methods in Applied Mechanics and Engineering 260 (June 2013): 130–42. http://dx.doi.org/10.1016/j.cma.2013.03.023.

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Baranitharan, Mathalaimuthu, Mahmoud Kandeel, Govindan Shanmugavel, Kumaravel Kaliyaperumal, Kumaran Subramanian, Kuppusamy Elumalai, Jayapal Gokulakrishnan, Hari Irrusappan, Senthil Rethinam, and S. Velmurugan. "Fabrication of Silver Nanoparticles Using Fimbristylis miliacea: A Cheap and Effective Tool against Invasive Mosquito Vector, Aedes albopictus." Journal of Nanomaterials 2022 (June 30, 2022): 1–9. http://dx.doi.org/10.1155/2022/4083663.

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Mosquitoes are the most critical group of insects in the context of public health, since they transmit key parasites and pathogens, causing millions of deaths annually. Aedes albopictus is an important invasive mosquito vector of dengue fever across urban and semiurban areas of India. In this study, we biofabricated silver nanoparticles (AgNPs) using the Fimbristylis miliacea aqueous leaf extract (Fm-ALE) as reducing and stabilizing agent. The synthesis of Fm-AgNPs was confirmed by the excitation of surface plasmon resonance and orange-brown color using ultraviolet-visible (UV-vis) spectrophotometry. High-resolution scanning electron microscopic (HR-SEM) and transmission electron microscopic (TEM) showed the clustered (size 0.5 μm) and quasi-spherical structures of Fm-AgNPs. The formation of AgNPs has been characterized by X-ray diffraction (XRD) spectroscopy. Fourier transform infrared (FTIR) spectroscopy investigated the identity of secondary metabolites, which may act as Fm-AgNP capping agents. These results propose that AgNPs synthesized provided from those Fm-ALE have the high sources to be improved into the most suitable materials useful for protecting and killing the invasive mosquito vector, Ae. albopictus populations. The acute toxicity of Fm-ALE synthesized Ag NPs, and a combined treatment testing blends of mosquito vector was evaluated against I, II, III, and IV instar larva’s (ILs) of Ae. albopictus. The LC50 values of Fm-ALE (174.39 ppm I-ILs, 214.40 ppm II-ILs, 232.38 ppm III-ILs, and 251.62 ppm IV-ILs) and Fm-AgNPs synthesized were 23.78 ppm I-ILs; 27.88 ppm II-ILs; 31.47 ppm III-ILs; 36.68 ppm IV-ILs, respectively. Likewise, Fm-AgNP synthesis was more toxic than ALE in the invasive mosquito vector and recorded from UV-vis spectrum, FTIR, TEM, and XRD analysis. These results propose that AgNPs synthesized provided from those Fm-ALE have the high sources to be improved into the most suitable materials useful for protecting and killing the invasive mosquito vector, Ae. albopictus populations.

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Dobkowska, Ada. "Zarząd w spółce partnerskiej – charakter prawny." Kortowski Przegląd Prawniczy, no. 4 (January 22, 2024): 5–12. http://dx.doi.org/10.31648/kpp.9130.

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Chociaż spółka partnerska jest spółką osobową, to można w niej powołać zarząd na mocy art. 97 § 1 k.s.h. Od kilkunastu lat toczy się spór, czym taki zarząd jest - występują w tej kwestii cztery poglądy. Przedstawiciele pierwszego poglądu wskazują, że członkowie zarządu to przedstawiciele ustawowi spółki partnerskiej. Propagatorzy drugiego poglądu przyjmują, że członkowie zarządu są przedstawicielami statutowymi, ale koncepcja ta jest raczej mniejszościowa. Zwolennicy trzeciej teorii przyjmują z kolei, że zarząd jest organem, tak jak chociażby zarząd w spółce z ograniczoną odpowiedzialnością, a czwarty – raczej dominujący w doktrynie – wskazuje, że jest quasi-organem. Najpopularniejsze są dwa ostatnie poglądy, jednak to teoria o quasi-organie jest popierana przez większość znawców prawa handlowego. W artykule przytoczone zostaną argumenty i kontrargumenty opowiadające się za każdą z tych koncepcji, a także wskazano praktyczne skutki wybrania danej interpretacji.

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Oger, G., S. Marrone, D. Le Touzé, and M. de Leffe. "SPH accuracy improvement through the combination of a quasi-Lagrangian shifting transport velocity and consistent ALE formalisms." Journal of Computational Physics 313 (May 2016): 76–98. http://dx.doi.org/10.1016/j.jcp.2016.02.039.

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Karasińska, Marta. "Od opisu do opsis." Forum Poetyki 20 (October 13, 2020): 6–17. http://dx.doi.org/10.14746/fp.2020.20.24899.

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Kompozycyjna kategoria opisu i szerzej rozumianej opisowości w dramacie pozostawała zawsze na marginesie dyskursu teoretycznoliterackiego. Tymczasem przejawiające się w nim modele deskrypcji, w związku z jego docelowym scenicznym przeznaczeniem, nie tylko wykazują się bogactwem artykulacji, ale także stanowią element sine qua non konstytuowania rzeczywistości przedstawionej. Obejmuje ona trzy modele przestrzenne: przestrzeń sceniczną, przysceniczną (przyległą) i relacjonowaną. Najbardziej typowa dla dramatu okazuje się forma opisu bezpośredniego zawarta bądź w didaskaliach, bądź w tekście głównym. Istotną rolę w kreowaniu prezentowanego świata odgrywa jednak także zawarty w wypowiedziach postaci, rozproszony opis pośredni (quasi-opis) czy ponadjęzykowa już opisowość realizowana z wyłączeniem semantyki słowa.

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Більше джерел

Дисертації з теми "Quasi-ALE"

Jaffal, Moustapha. "Développement de Dépôt Sélectif Topographique 3D par combinaison de procédés PE(ALD) et ALE en microélectronique." Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALT046.

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Au cours des dernières décennies, l’industrie des semi-conducteurs a connu une augmentation spectaculaire de la performance des circuits intégrés. La photolithographie, un procédé indispensable à la fabrication des circuits intégrés, requiert désormais une séquence d'étapes de plus en plus complexes, comprenant de nombreux traitements successifs tels que le Self-Aligned Double Patterning (SADP) et le Self-Aligned Quadruple Patterning (SAQP). Au-delà de leur complexité et de l’augmentation des coûts associés, les étapes de patterning engendrent des erreurs d’alignement (Edge Placement Error (EPE)) qui affectent le bon fonctionnement des dispositifs. L’objectif de la thèse est de développer un nouveau procédé de dépôt sélectif topographique (TSD) par une approche en super-cycle « Dépôt/Gravure ». Les avantages d’un dépôt TSD est de réaliser latéralement et directement des espaceurs sur les flancs latéraux des architectures 3D telles que les grilles des transistors CMOS à l’échelle du nanomètre. Cette nouvelle stratégie de fabrication permet tout d’abord d’envisager une réduction du nombre des étapes et d’équipements nécessaires à la structuration, limitant ainsi les EPE potentiellement induites par la photolithographie. Ainsi, elle offre la possibilité de réduire la consommation des surfaces horizontales des transistors 3D, qui est un des éléments critiques à prendre en compte lors de réalisation des espaceurs dans l’intégration des nœuds technologiques avancés. Une preuve de concept du dépôt TSD a fait l’objet de ma thèse grâce à une approche en super-cycle reposée sur l’alternance d’un procédé de dépôt conforme par PE(ALD) suivi par différents procédés de gravure plasma anisotrope dans un seul et même équipement, en utilisant les propriétés physiques et chimiques d’interactions des plasmas avec les matériaux
Over the past decades, the semiconductor industry has witnessed a remarkable increase in the performance of integrated circuits. Photolithography, a crucial process in the manufacturing of integrated circuits, requires an increasingly complex sequence of steps, including various successive treatments such as Self-Aligned Double Patterning (SADP) and Self-Aligned Quadruple Patterning (SAQP). Beyond their complexity and the associated cost escalation, patterning steps can result in alignment errors, known as Edge Placement Error (EPE), which can impact the proper functioning of devices such as transistors. The objective of this thesis is to develop a novel topographical selective deposition (TSD) process using a "Deposition/Etching" super-cycle approach. The advantages of this TSD process include the lateral and direct formation of spacers on the sidewalls of 3D architectures, such as CMOS transistor gates at the nanoscale. This innovative manufacturing approach paves the way for reducing the number of steps and equipment required in the fabrication process, minimizing the potential EPE introduced by photolithography. Consequently, it offers the opportunity to reduce the consumption of horizontal surfaces in 3D transistors, a critical factor in the integration of advanced technological nodes during spacer creation. This work offers a proof of concept of the TSD deposition, using a super-cycle approach that alternates between a conformal deposition process by PE(ALD) and various anisotropic plasma etching processes in the same tool. This approach leverages the physical and chemical properties of plasma interactions with materials

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Beckstein, Pascal. "Methodenentwicklung zur Simulation von Strömungen mit freier Oberfläche unter dem Einfluss elektromagnetischer Wechselfelder." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-232474.

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Im Bereich der industriellen Metallurgie und Kristallzüchtung treten bei zahlreichen Anwendungen, wo magnetische Wechselfelder zur induktiven Beeinflussung von leitfähigen Werkstoffen eingesetzt werden, auch Strömungen mit freier Oberfläche auf. Das Anwendungsspektrum reicht dabei vom einfachen Aufschmelzen eines Metalls in einem offenen Tiegel bis hin zur vollständigen Levitation. Auch der sogenannte RGS-Prozess, ein substratbasiertes Kristallisationsverfahren zur Herstellung siliziumbasierter Dünnschichtmaterialien, ist dafür ein Beispiel. Um bei solchen Prozessen die Interaktion von Magnetfeld und Strömung zu untersuchen, ist die numerische Simulationen ein wertvolles Hilfsmittel. Für beliebige dreidimensionale Probleme werden entsprechende Berechnungen bisher durch eine externe Kopplung kommerzieller Programme realisiert, die für Magnetfeld und Strömung jeweils unterschiedliche numerische Techniken nutzen. Diese Vorgehensweise ist jedoch im Allgemeinen mit unnötigem Rechenaufwand verbunden. In dieser Arbeit wird ein neu entwickelter Methodenapparat auf Basis der FVM vorgestellt, mit welchem sich diese Art von Berechnungen effizient durchführen lassen. Mit der Implementierung dieser Methoden in foam-extend, einer erweiterten Version der quelloffenen Software OpenFOAM, ist daraus ein leistungsfähiges Werkzeug in Form einer freien Simulationsplattform entstanden, welches sich durch einen modularen Aufbau leicht erweitern lässt. Mit dieser Plattform wurden in foam-extend auch erstmalig dreidimensionale Induktionsprozesse im Frequenzraum gelöst.

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Beckstein, Pascal. "Methodenentwicklung zur Simulation von Strömungen mit freier Oberfläche unter dem Einfluss elektromagnetischer Wechselfelder." Doctoral thesis, 2017. https://tud.qucosa.de/id/qucosa%3A30749.

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Частини книг з теми "Quasi-ALE"

Joyce, Dominic D. "Quasi-Ale Metrics With Holonomy Su(M) And Sp(M)." In Compact Manifolds with Special Holonomy, 203–41. Oxford University PressOxford, 2000. http://dx.doi.org/10.1093/oso/9780198506010.003.0009.

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Abstract Let G be a finite subgroup of U(m) and suppose (X,π) is a resolution of Cm/G. In the case in which G acts freely on Cm\ (0), so that Cm/G has an isolated quotient singularity at 0, Chapter 8 defined a special class of Kähler metrics on X called ALE Kähler metrics, and proved an existence result for Ricci-flat ALE Kähler metrics. We will now generalize these ideas to the case when G does not act freely on Cm \(0) , so that the singularities of Cm/G are not isolated.

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Тези доповідей конференцій з теми "Quasi-ALE"

Lai, Panpan, Junjie Li, Hua Shao, Rui Chen, and Yayi Wei. "Study of precisely controlled selective isotropic quasi-ALE of SiGe." In Advanced Etch Technology and Process Integration for Nanopatterning XIII, edited by Efrain Altamirano-Sánchez and Nihar Mohanty. SPIE, 2024. http://dx.doi.org/10.1117/12.3010886.

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Pascuzzo, A. "Numerical modeling of dynamic crack propagation mechanisms using a moving mesh technique based on the ALE formulation." In AIMETA 2022. Materials Research Forum LLC, 2023. http://dx.doi.org/10.21741/9781644902431-44.

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Abstract. This work proposes a new FE model to predict dynamic crack propagation mechanisms in quasi-brittle materials. The numerical strategy uses a Moving Mesh (MM) technique consistent with the Arbitrary Lagrangian-Eulerian (ALE) formulation to reproduce the variation of the geometry of the computational domain caused by dynamically growing cracks. Specifically, the motion of the mesh nodes takes place consistently with conditions dictated by classic Fracture Mechanics, which provide conditions concerning the direction of propagation and the velocity of advancing cracks. As a remarkable key novelty, the proposed method introduces the ALE formulation of the M-integral for extracting Dynamic Stress Intensity Factors (DSIFs) at a moving crack front. This formulation allows extracting fracture variables on deforming elements without losing accuracy. Comparisons with analytical and numerical data are proposed to assess the validity and efficiency of the proposed strategy.

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Fox, D. M., and J. S. Lee. "Application of an Arbitrary Lagrangian Eulerian Method to Describe High Velocity Gas-Particle Flow Behavior." In ASME-JSME-KSME 2011 Joint Fluids Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajk2011-03075.

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Novel computational and small-scale experimental investigations were performed in order to better understand the high velocity flow behavior of gas-particle mixtures. The motion of solid objects impacted by the flow of the mixtures was measured by use of high-speed digital video photography. Computations were performed by use of an arbitrary Lagrangian Eulerian (ALE) treatment in a nonlinear finite element code. Constitutive models for description of the solid component of the gas-particle blend were developed based on quasi-statically determined test results. It was observed that there was very close agreement between experimental and computational results and that it was possible to accurately predict the high velocity flow behavior of the gas-particle mixture using quasi-statically determined constitutive models.

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Asako, Yutaka, and Kenji Nakayama. "Effect of Compressibility on Gaseous Flows in a Micro-Tube." In ASME 2003 Heat Transfer Summer Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/ht2003-47166.

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The product of friction factor and Reynolds number (f·Re) of gaseous flow in the quasi-fully developed region of a micro-tube was obtained experimentally and numerically. The tube cutting method was adopted to obtain the pressure distribution along the tube. The fused silica tubes whose nominal diameters were 100 and 150 μm, were used. Two-dimensional compressible momentum and energy equations were solved to obtain the flow characteristics in micro-tubes. The numerical methodology is based on the Arbitrary-Lagrangian-Eulerian (ALE) method. The both results agree well and it was found that (f·Re) is a function of Mach number.

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Hong, Chungpyo, Yutaka Asako, and Mohammad Faghri. "Friction Factor Correlations of Slip Flow in Micro-Tubes." In ASME 2007 5th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2007. http://dx.doi.org/10.1115/icnmm2007-30064.

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Poiseuille number, the product of friction factor and Reynolds number (f·Re) for quasi-fully developed flow in a micro-tube was obtained in slip flow regime. The numerical methodology is based on the Arbitrary-Lagrangian-Eulerian (ALE) method. Two-dimensional compressible momentum and energy equations were solved for a wide range of Reynolds and Mach numbers with two thermal boundary conditions: CWT (constant wall temperature) and CHF (constant heat flux), respectively. The tube diameter ranges from 3 to 10μm and the tube aspect ratio is 200. The stagnation pressure, pstg is chosen in such away that the exit Mach number ranges from 0.1 to 1.0. The outlet pressure is fixed at the atmospheric pressure. In slip flow, Mach and Knudsen numbers are systematically varied to determine their effects on f·Re. The correlation for f·Re is obtained from numerical results. It was found that f·Re is mainly a function of Mach number and Knudsen number and is different from the values obtained by 64/(1+8Kn) for slow flow. The obtained f·Re correlations are applicable to both no-slip and slip flow regimes.

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Crouzet, Fabien, and Philippe Lafon. "Numerical Analysis of Flutter in a Transonic Low Pressure Steam Turbine." In ASME 2005 Pressure Vessels and Piping Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/pvp2005-71226.

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High levels of vibrations have been observed on the last row blades of a low pressure steam turbine for nominal operating conditions. A self-excited phenomenon known as flutter is suspected to be the cause of the vibrations for non-stall transonic conditions. The non-homogeneous distribution of vibratory levels on the row is attributed to mistuning effects. They are beyond the scope of our study. A time-dependent ALE formulation of Euler equations is derived on a quasi-3D domain and coupled with a one-degree-of-freedom structural model. The work-by-cycle (WBC) method is performed in order to analyse the stability of the vibrating blades in the surrounding flowfield, for a perfectly tuned assembly. On the top part of the blades, the flow is transonic and fully attached. It is shown that, for these operating conditions, the cascade aeroelastic behaviour is linear. By using the influence coefficient method, an instability region is exhibited. The effects of the flowfield on the vibrating blades are discussed. They are expressed in terms of added damping and stiffness in order to be used as the input data of a structural mistuning analysis.

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Hong, Chungpyo, Yutaka Asako, and Koichi Suzuki. "Poiseuille Number Correlations of Gas Flow in Concentric Micro Annular Tubes." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-67127.

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Poiseuille number, the product of friction factor and Reynolds number (f · Re) for quasi-fully developed concentric micro annular tube flow was obtained for both no-slip and slip boundary conditions. The numerical methodology is based on the Arbitrary-Lagrangian-Eulerian (ALE) method. The compressible momentum and energy equations were solved for a wide range of Reynolds and Mach numbers for both isothermal flow and no heat conduction flow conditions. The detail of the incompressible slip Poiseuille number is kindly documented and its value defined as a function of r* and Kn is represented. The outer tube radius ranges from 50 to 150μm with the radius ratios of 0.2, 0.5 and 0.8 and selected tube length is 0.02m. The stagnation pressure, pstg is chosen in such away that the exit Mach number ranges from 0.1 to 0.7. The outlet pressure is fixed at the atmospheric pressure. In the case of fast flow, the value of f · Re is higher than that of incompressible slip flow theory due to the compressibility effect. However in the case of slow flow the value of f · Re is slightly lower than that of incompressible slip flow due to the rarefaction effect, even the flow is accelerated. The value of f · Re obtained for no-slip boundary conditions is compared with that of obtained for slip boundary conditions. The values of f · Re obtained for slip boundary conditions are predicted by f · Re correlations obtained for no-slip boundary conditions since rarefaction effect is relatively small for the fast flow.

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Hong, Chungpyo, Yutaka Asako, and Koichi Suzuki. "Friction Factor Correlations of Gas Slip Flow in Concentric Micro Annular Tubes." In ASME 2009 7th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2009. http://dx.doi.org/10.1115/icnmm2009-82089.

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A concentric micro annular passage is a basic and important micro-geometry of micro-fluidic-systems from simple heat exchangers to the most complicated nuclear reactors. Therefore, the product of friction factor and Reynolds number (f·Re) for quasi-fully developed high speed and slip flow in a concentric micro annular tubes of Re<1000 and Ma<1.0 was obtained numerically. The numerical methodology was based on the Arbitrary-Lagrangian-Eulerian (ALE) method. The compressible momentum and energy equations with slip boundary conditions were solved for both isothermal flow and no-heat conduction flow conditions. The outer tube radius ranged from 5 to 40 μm with the radius ratios of 0.2, 0.5 and 0.8. The ratio of length to hydraulic diameter was 100. The stagnation pressure was chosen in such a way that the exit Mach number ranged from 0.1 to 1.0. The outlet pressure was fixed at the atmospheric pressure. The value of f·Re for compressible slip flow in concentric micro annular tubes were obtained. The detail of the incompressible slip f·Re is documented and its value defined as a function of r* and Kn is represented. The results show that in the case of fast flow, the values of f·Re for compressible slip flow is higher than those for incompressible slip flow due to compressibility effects. Also, the f·Re correlation for compressible slip flow is obtained from that of compressible no-slip flow and incompressible slip flow as a function of Mach and Knudsen numbers and radius ratio. In addition, a f·Re correlation from the values of f·Re obtained for micro-channel, micro-tube, and micro annular tube referred in author’s previous works that is applicable to micro-geometries whose cross-sections are parallel, rectangular, circular and annular, is proposed.

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Hamada, Ahmed A., Lubna Margha, Mohamed M. AbdelRahman, and Amr Guaily. "Shock System Dynamics of a Morphing Bump Over a Flat Plate." In ASME 2022 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/fedsm2022-87504.

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Abstract The shock wave boundary layer interaction (SW-BLI) phenomenon over transonic and supersonic airfoils captured the attention of aerospace engineers, due to its disastrous effect on the aerodynamic performance of these vehicles. Thus, the scientific community numerically and experimentally investigated several active and passive flow control elements to reduce the effect of the phenomenon, such as vortex generator, cavity, and bump. They focused on designing and optimizing the shape and location of the bump control element. However, the transit movement of the bump from the state of a clean airfoil to the state of an airfoil with a bump needs more investigation, especially the dynamics of the shock system. Thus, it is preferred to start with simple geometry, such as a flat plate, to fully understand the flow behavior with a morphing bump. In this paper, the shock dynamics due to the movement of a bump over a flat plate flying at supersonic speed are numerically investigated. The bump is located at the impingement position of the shock wave and is moved at different speeds. This study determines the suitable speed that achieves the minimum entropy change, which is the representation parameter of the transition period. The two-dimensional unsteady Navier-Stokes equations are solved using OpenFOAM to simulate the flow field variables, while the motion of the bump is tracked using the Arbitrary Lagrangian-Eulerian (ALE) technique. The results show that a spatial lag on the shock system from the steady-state solution occurs due to the movement of the bump. Further, the spatial lag increases with the increase in the bump’s speed. This causes a high increase in the flow parameters and consequently the total entropy changes on the bump surface. Generally, it is common to move the bump over the longest possible time to approximate a quasi-steady flow during the motion. However, this causes a deviation in the flow parameters between the final time of transition and the steady-state case of bump existence. Thus, it is concluded that the optimal non-dimensional time for a morphing bump in a supersonic flow of Mach number of 2.9 is 2, which is different than the longest time of 10.

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Torczynski, John R., Timothy J. O’Hern, Jonathan R. Clausen, and Timothy P. Koehler. "Gas-Induced Motion of an Object in a Liquid-Filled Housing During Vibration: Part I — Analysis." In ASME 2017 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/fedsm2017-69022.

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Models and simulations are employed to analyze the motion of a spring-supported piston in a vibrated liquid-filled cylinder. The piston motion is damped by forcing liquid through a narrow gap between a hole through the piston and a post fixed to the housing. As the piston moves, the length of this gap changes, so the piston damping coefficient depends on the piston position. This produces a nonlinear damper, even for highly viscous flow. When gas is absent, the vibration response is overdamped. However, adding a little gas changes the response of this spring-mass-damper system to vibration. During vibration, Bjerknes forces cause some of the gas to migrate below the piston. The resulting pneumatic spring enables the liquid to move with the piston so as to force very little liquid through the gap. Thus, this “Couette mode” has low damping and a strong resonance near the frequency given by the pneumatic spring constant and the total mass of the piston and the liquid. Near this frequency, the amplitude of the piston motion is large, so the nonlinear damper produces a large net force on the piston. To analyze the effect of this nonlinear damper in detail, a surrogate system is developed by modifying the original system in two ways. First, the gas regions are replaced by upper and lower bellows with similar compressibility to give a well-defined “pneumatic” spring. Second, the upper stop against which the piston is pushed by its lower supporting spring is replaced with an upper spring, thereby removing the nonlinearity from the stop. An ordinary-differential-equation (ODE) drift model based on quasi-steady Stokes flow is used to produce a regime map of the vibration amplitudes and frequencies for which the piston is up or down for conditions of experimental interest. These results agree fairly well with Arbitrary Lagrangian Eulerian (ALE) simulations of the incompressible Navier-Stokes (NS) equations for the liquid and Newton’s 2nd Law for the piston and bellows. A quantitative understanding of this nonlinear behavior may enable the development of novel tunable dampers for sensing vibrations of specified amplitudes and frequencies.

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