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Numerical Modelling of the Aeroelastic Behaviour and variable Loads for the Turbine Stage in 3D Transonic Flow

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Journal of Thermal Science 2005年第3期14卷 236-241页

作者： v.i. GNESiN L.v. KOLODYAZHNAYA R. RZADKOWSKi Department of Aerohydromechanics Institute of Mechanical Engineering Problems National Academy of Sciences of Ukraine 2/10 Pozharsky st. Kharkov 61046 Ukraine ProfessorDepartment of Aerohydromechanics Institute of Mechanical Engineering Problems National Academy of Sciences of Ukraine 2/10 Pozharsky st. Kharkov 61046 UkraineDepartment of Dynamics of Machines Institute of Fluid Flow Machinery Polish Academy of Sciences J. Fiszera st. 14 Gdansk 80 952 Poland

in this study presented the algorithm proposed involves the coupled solution of 3-D unsteady flow through a turbine stage and the dynamics problem for rotor-blade motion by the action of aerodynamic forces, without separating the outer and inner flow fluctuations. The partially integrated method involves the solution of the fluid and structural equations separately, but information is exchanged at each time step, so that solution from one domain is used as a boundary condition for the other domain. 3-D transonic gas flow through the stator and rotor blades in relative motion with periodicity on the whole annulus is described by the unsteady Euler conservation equations, which are integrated using the explicit monotonous finite-volume difference scheme of Godunov-Kolgan. The structural analysis uses the modal approach and a 3-D finite element model of a blade. A calculation has been done for the last stage of the steam turbine, under design and off-design regimes. it is shown that the amplitude-frequency spectrum of blade oscillations contains the high frequency harmonics, corresponding to the rotor moving past one stator blade pitch, and low frequency harmonics caused by blade oscillations and flow nonuniformity downstream from the blade row; moreover, the spectrum involves the harmonics which are not multiples of the rotation frequency.

关键词： turbine stage 3D unsteady flow blade oscillations

importance of charge self-consistency in first-principles description of strongly correlated systems

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npj Computational Materials 2021年第1期7卷 1949-1956页

作者： Swagata Acharya Dimitar Pashov Alexander N.Rudenk Malte Rösner Mark van Schilfgaarde mikhail i.Katsnelson institute for Molecules and Materials Radboud UniversityNijmegen 6525 AJThe Netherlands Theory and Simulation of Condensed Matter King's College LondonThe StrandLondon WC2R2LSUK National Renewable Energy Laboratory Golden80401 ColoradoUSA

First-principles approaches have been successful in solving many-body Hamiltonians for real materials to an extent when correlations are weak or *** the electronic correlations become stronger often embedding methods based on first-principles approaches are used to better treat the correlations by solving a suitably chosen many-body Hamiltonian with a higher level *** success of such embedding theories,often referred to as second-principles,is commonly measured by the quality of self-energy E which is either a function of energy or momentum or ***,E should,in principle,also modify the electronic eigenfunctions and thus change the real space charge *** such practices are not prevalent,some works that use embedding techniques do take into account these *** such cases,choice of partitioning,of the parameters defining the correlated Hamiltonian,of double-counting corrections,and the adequacy of low-level Hamiltonian hosting the correlated subspace hinder a systematic and unambiguous understanding of such ***,for a large variety of correlated systems,strong correlations are largely confined to the charge *** an adequate non local low-order theory is important,and the high-order local correlations embedding contributes become *** we study the impact of charge self-consistency within two example cases,TiSez and CrBrs,and show how real space charge re-distribution due to correlation effects taken *** within a first-principles Green's function-based many-body perturbative approach is key in driving qualitative changes to the final electronic structure of these materials.

关键词： theory charge principles

Prolonged intermittent theta burst stimulation restores the balance between A_(2A)R-and A_(1)R-mediated adenosine signaling in the 6-hydroxidopamine model of Parkinson's disease

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Neural Regeneration Research 2025年第7期20卷 2053-2067页

作者： Milica Zeljkovic Jovanovic Jelena Stanojevic ivana Stevanovic Milica Ninkovic Tihomir v.ilic Nadezda Nedeljkovic Milorad Dragic Laboratory for Neurobiology Department of General Physiology and BiophysicsFaculty of BiologyUniversity of BelgradeBelgradeSerbia Medical Faculty of Military Medical Academy University of DefenceBelgradeSerbia

An imbalance in adenosine-mediated signaling,particularly the increased A_(2A)R-mediated signaling,plays a role in the pathogenesis of Parkinson's *** therapeutic approaches fail to alter disease progression,demonstrating the need for novel approaches in *** transcranial magnetic stimulation is a non-invasive approach that has been shown to improve motor and non-motor symptoms of Parkinson's ***,the underlying mechanisms of the beneficial effects of repetitive transcranial magnetic stimulation remain *** purpose of this study is to investigate the extent to which the beneficial effects of prolonged intermittent theta burst stimulation in the 6-hydroxydopamine model of experimental parkinsonism are based on modulation of adenosine-mediated *** with unilateral 6-hydroxydopamine lesions underwent intermittent theta burst stimulation for 3 weeks and were tested for motor skills using the Rotarod ***,quantitative reverse transcription polymerase chain reaction,immunohistochemistry,and biochemical analysis of components of adenosine-mediated signaling were performed on the synaptosomal fraction of the lesioned caudate *** intermittent theta burst stimulation improved motor symptoms in 6-hydroxydopamine-lesioned animals.A 6-hydroxydopamine lesion resulted in progressive loss of dopaminergic neurons in the caudate *** with intermittent theta burst stimulation began 7 days after the lesion,coinciding with the onset of motor *** treatment with prolonged intermittent theta burst stimulation,complete motor recovery was *** improvement was accompanied by downregulation of the e N/CD73-A_(2A)R pathway and a return to physiological levels of A_(1)R-adenosine deaminase 1 after 3 weeks of intermittent theta burst *** results demonstrated that 6-hydroxydopamine-induced degeneration reduced the expression of A_(1)R and elevated the expression of A_(2A)***

关键词： A_(1)R A_(2A)R adenosine receptors adenosine ecto-5′-nucleotidase intermittent theta burst stimulation non-invasive brain stimulation Parkinson's disease purinergic signalling

Laminar Forced Convection in Curved Channel with vortex Structures

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Journal of Thermal Science 2004年第2期13卷 143-149,162页

作者： A.A. AvRAMENKO S.G. KOBZAR i.v. SHEvCHUK A.v. KUZNETSOv B.i. BASOK institute of Engineering Thermophysics National Academy of SciencesKievUkraine Center for Energy Research National University of MexicoAp.P.3462580TemixcoMor.Mexico Dept.of Mechanical and Aerospace Engineering North Carolina State UniversityCampus Box 7910RaleighNC 27606-7910USA

Theoretical and experimental investigations of heat transfer in flat curvilinear channel have been carried out. Linear and non-linear effects of Dean vortexes on intensity of heat transfer were taken into account. The linear effect, which describe harmonic (sinuous) variation of the heat transfer coefficient near the concave surface of the channel and the non-linear effect causes the general increase of the heat transfer coefficient due to augmentation of heat transfer engendered by the Dean vortexes. For both effects, mathematical relations were obtained in the form of quadratures. These numerical results were modified to the form convenient in engineering calculations. The investigations have shown that both linear and nonlinear components grow up with the Dean number. Nonlinear component Q0T increases more abruptly, while the linear one Q1T is more conservative. This is a confirmation of stability of vortex structures.

关键词： heat transfer Dean vortexes curvilinear channel quadrature.

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAURABH R.KiRAN D.SiNGH R.vAiSH v.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(iHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. various helicoidal layup configurations including helicoidal recursive(HR), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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Bending sensor based on flexible spin valve

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Chinese Physics B 2023年第5期32卷 655-661页

作者： L i Naumova R S Zavornitsyn M A Milyaev N G Bebenin A Y Pavlova M v Makarova i K Maksimova v v Proglyado A A Zakharov v v Ustinov M.N.Miheev institute of Metal Physics Ural BranchRussian Academy of SciencesS.Kovalevskoi Street 18Ekaterinburg 620990Russia

Flexible spin valves were prepared by magnetron sputtering on polyimide substrates. The buffer layer that reduces significantly the effect of the polymer substrate on the spin valve microstructure and magnetoresistive properties was revealed. Bending deformation was applied to the microobjects based on the flexible spin valves in parallel to anisotropy axes. it was revealed that during the bend the magnetoresistance changes due to the joint impact of both the change of the magnetic field projection on the film plane and the change of the magnetic properties of the ferromagnetic layers. The obtained dependences have been used in construction of bending sensor, in which the flexible spin valve microstripes were united into the Wheatstone bridge.

关键词： spin valve polymer substrate magnetostriction magnetic anisotropy

Correction of dispersion distortion of femtosecond pulses by using the non-planar surface of diffractive optical elements

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Chinese Optics Letters 2004年第8期2卷 435-437页

作者： i.v.Minin O.v.Minin Novosibirsk State Technical University Novosibirsk RussiaNovosibirsk State Technical University Novosibirsk Russia

Peculiarities of propagation of femtosecond pulses through a focusing diffractive optical element (DOE) are considered. it is shown that the time delay between the pulse and phase wavefronts can be decreased by fabric... 详细信息

关键词： Correction of dispersion distortion of femtosecond pulses by using the non-planar surface of diffractive optical elements DOE

Structural traits of woody plants and geomorphological conditions to the vegetation recovery at Ksudach caldera(Southern Kamchatka) since the explosive eruption in 1907

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Journal of Mountain Science 2020年第7期17卷 1613-1635页

作者： KOPANiNA Anna v LEBEDEvA Ekaterina v vLASOvA inna i TALSKiKH Anastasia v institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesNauka street1 B693022Yuzhno-SakhalinskRussia institute of Geography Russian Academy of SciencesStaromonetny s-str.29119017MoscowRussia

This study considers the restoration of the plant cover destroyed by a catastrophic volcano eruption in the south of Kamchatka Peninsula(the Ksudach caldera,Shtyubel cone),with a particular attention to the role of woody *** aims to qualitatively estimate(at a qualitative level)the rate of the primary succession development depending on the microrelief and the modern relief-forming *** vegetation recovery in the caldera after the Shtyubel cone eruption 109 years ago proceeds slowly and *** proceeds most slowly on a thick tephra mantle continuously disturbed by water and wind erosion,lahars,debris flows,landslides,*** conditions are most typical of the western part of the caldera dominated by pumice fields with occasional patches of pioneer herbs and dwarf *** tundra communities with gradually expanding patches of shrub alder develop in the southern,eastern and northeastern parts of the Ksudach *** 1997 the area of the shrub alder communities has increased by 1.9 times,while the alpine tundra–by 1.3 times *** woody plants(dwarf shrubs and prostrate shrubs)are of particular importance in the process of the vegetation recovery on pumice *** suggest that the bark thickness of woody plants is an integrated indicator,which may serve for estimating the state of ecosystem in the course of the primary succession development on juvenile *** extremely inhospitable environments cause changes in physiological processes in the plant body and in its bark in *** results show that woody plants have a"thin"bark and develop some structural-functional arrangements for keeping bark tissues at their ***,the woody plant structure and the rate of changes in plant communities are under control of the geomorphic conditions and primarily–of physicochemical features of the pyroclastic cover.

关键词： Ksudach caldera Pioneer species Woody plants Bark Pyroclastic deposits Geomorphological processes

Thermal Response of Mould in High Speed Casting of Stainless Steel Billet

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Journal of iron and Steel Research international 2002年第2期9卷 15-20页

作者： WANG Bao-feng SAMARASEKERA i v Baotou University of iron and Steel Tech University of British Columbia

The hot rolling of slab was studied with the aid of elastic plastic and thermomechanical couple FEM. On the basis of experiment and numerical analysis, the physical models for interfacial heat transfer during hot rolling were established. The results indicated that the deformation, cracking and decohesion behavior of the oxide scale have considerable effects on temperature distribution of slab during hot rolling.

关键词： interfacial heat transfer oxide scale temperature distribution hot rolling