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An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.v.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Electric field distributions along helium plasma jets

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High voltage 2020年第6期5卷 650-653页

作者： george v.naidis Natalia Yu Babaeva Joint Institute for High Temperatures RAS 125412 MoscowRussia

Results of simulations of streamers propagating along the atmospheric-pressure helium plasma jets ejected from a thin tube into ambient air are presented. The computational model includes the equations governing the helium-air mixture composition along and across the jet, as well as the equations, describing streamer propagation in the mixture, for the electric field and the charged species densities. Streamer velocity and spatial-temporal profiles of plasma parameters are obtained for various values of the helium flow rate. It is shown, in agreement with available experimental data, that the electric field values in the heads of streamers increase nearly linearly with the distance from the tube exit and that the slope of this dependence decreases with the growth of the helium flow rate.

关键词： field mixture ambient

Structure of low-head two-phase flow in flat nozzlesduring outflow of the liquid into rarefied medium

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航空动力学报 2011年第10期26卷 2188-2192页

作者： Kochenkov A g Tonkonog v g Kazan State Technical University named after A. N. Tupolev Kazan Russian Federation

Outcomes of experimental researches of the low-pressure adiabatic flow of the boiling liquid through two-dimensional Laval nozzles in a vacuum atmosphere were *** of critical conditions of flow were *** forms of a stream were investigated and their connection with crisis of flow was *** was established periodic non-stationary macrostructures of a stream which was stipulated by the rotational gear of origin of a vapor phase.

关键词： component low-head flow flow structure flat nozzle rarefied medium the mechanizm of vaporization mass flow rate

Numerical 3D Model of viscous Turbulent Flow in One Stage gas Turbine and Its Experimental validation

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Journal of Thermal Science 2005年第2期14卷 136-141页

作者： Yu.v.STARODUBTSEv I.g.gOgOLEv v.g.SOLODOv National Technical University "KhADI" Ukraine Briansk State Technical University <BITM> RussiaNational Technical University "KhADI" Ukraine

The paper describes 3D numerical Reynolds Averaged Navier-Stokes (RANS) model and approximate sector approach for viscous turbulent flow through flow path of one stage axial supercharge gas turbine of marine diesel engine. Computational data are tested by comparison with experimental data. The back step flow path opening and tip clearance jet are taken into *** approach could be applied for variety of turbine theory and design tasks: for offer optimal design in order to minimize kinetic energy stage losses; for solution of partial supply problem; for analysis of flow pattern in near extraction stages; for estimation of rotational frequency variable forces on blades; for sector vane adjustment (with thin leading edges mainly), for direct flow modeling in the turbine etc. The development of this work could be seen in the direction of unsteady stage model application.

关键词： viscous turbulent flow one stage gas turbine tip leakage flow secondary flow.

Zonal Metamorphic Complex in the Tongulack Mountain Ridge, Altai, Russia, and Explanation ofIts Origin with the Help of Thermal Modelling

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Acta geologica Sinica(English Edition) 1998年第1期72卷 51-64页

作者： g.g.Lepezin v.v.Reverdatto United Institute of geology Geophysics and MineralogySiberian Branch of Russion Academy of SciencesAcademician Koptyug prospect3 Novosibirsk 630090Russia

A moderate pressure/high temperature zonal metamorphic complex in the Tongulack Mountain Ridge, Altai, Russia, is described, and the applicability of the models of magmatic intrusion and fluid flow to explanation of its origin discussed. The Precambrian complex was formed at 500–700°C and 3.0–5.5 kbars; it is a linear, 25–30 km wide, thermal anticline with a curved axis showing symmetric metamorphic zoning. The metamorphism was isochemical by its nature, as is corroborated by the chemical compositions of the rocks. Four zones can be recognized within the metamorphic complex: chloritic (on the peripheries), cordieritic, sillimanitic and staurolite-out (in the centre). The zones are separated by successive isograds: cordierite, staurolite-in or sillimanite and staurolite-out. It is argued that the origin of the metamorphic zoning can be explained best by a combined fluid-magmatic model; conductive heat flow from the intrusion predominated considerably over the fluid flux in heat transfer: the fluid flow rate was estimated as about 3 ? 10?9 g/cm2, ? s. The modern position of the axial region of the metamorphic belt is predicted to be lying roughly about 1.5 km above the roof of the intrusive body.

关键词： Tongulack complex Altai Russia moderate pressure/high temperature zonal metamorphism heat transfer modelling

Surface integrity of ball burnished bioresorbable magnesium alloy

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Advances in Manufacturing 2023年第2期11卷 342-362页

作者： g.v.Jagadeesh Srinivasu gangi Setti Department of Mechanical Engineering National Institute of Technology RaipurChhattisgarh492010India

Magnesium alloys are potential biodegradable and biocompatible implant materials because of their excellent biological properties. Recently, interest in these alloys as a promising alternative for temporary orthopedic implants has grown owing to their desirable biological, mechanical, and physical properties. However, the application of magnesium alloys is hindered by their rapid degradation and low corrosion resistance in physiological fluids, leading to the failure of implants. Thus, the current challenge is to enhance the corrosion resistance and control the degradation rate of magnesium under physiological conditions. The rapid degradation of magnesium alloys can be controlled by improving their surface integrity, such as surface roughness and microhardness. The present study aims to improve the surface integrity of the Mg Ze41A alloy by the ball burnishing technique. The surface roughness improved by 94.90% from 0.941 μm to 0.048 μm with a burnishing force of 50 N, burnishing speed of 1 300 r/min, burnishing feed of 130 mm/min, and three passes. Similarly, the microhardness improved by 50.62% from 75.2 Hv to 113.27 Hv with a burnishing force of 60 N, burnishing speed of 1 100 r/min, burnishing feed of 100 mm/min, and five passes. The variations in microhardness, which were observed up to 400 μm beneath the surface, exhibited a linear nature. These variations may be attributed to the movement of dislocations, formation of new dislocations, nanocrystal structures, metastable phases and subgrains, and lattice distortion or grain refinement. The surface features obtained from optical images demonstrated the fundamental mechanisms involved in the ball burnishing process. The concept of burnishing maps and zones will assist in the design of the ball burnishing parameters of a material with an equivalent yield strength of 140 MPa. The significant improvement in the surface integrity of the Mg Ze41A alloy by the ball burnishing technique is expected to improve its func

关键词： Magnesium alloy Bioresorbable Orthopedic implants Surface integrity Ball burnishing

Stability of Macroscopic Binary Systems

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Communications in Theoretical Physics 2019年第11期71卷 1335-1340页

作者： g.g.Adamian N.v.Antonenko H.Lenske v.v.Sargsyan Joint Institu te for Nuclear Research 141980 DubnaRussia Ins titut fur Theore tische Physik der Jus tus-Liebig—Uni versit Nt D-35392 GiessenGermany

The Darwin instability effect in the binary systems(di-planets, di-stars, and di-galaxies) is analyzed within the model based on the Regge-like laws. All possible binary stars are found satisfying the Darwin instability condition that requires to search for other mechanism triggering the merger of the contact binary objects. New analytical formulas are obtained for the orbital rotation period and the relative distance between components of the binary system. The decreasing and increasing periods as functions of mass asymmetry are related, respectively, with the non-overlapping and overlapping stage of the binary object evolution.

关键词： Regge laws binary stars and galaxies Darwin instability effect

Synthesis of Pharmaceutical Intermediates by Toluene Benzylation over Heteropoly Acids on Different Support

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Journal of Natural gas Chemistry 2007年第2期16卷 186-192页

作者： v. v. Bokade g. D. Yadav Catalysis Division National Chemical LaboratoryPune 411008India University Institute of Chemical TechnologyMumbai-19India University Institute of Chemical Technology Mumbai-19India

Selective formation of pharmaceutical intermediates like diphenylmethane, dimethyldiphenylmethane, benzyl toluene and benzoic acid by liquid phase, toluene benzylation with benzyl chloride as a benzylating agent, was systematically studied over plane clay （K-10, montmorillonite）, plane H-Beta, plane MFI structured titanosilicate （TS-1） and heteropoly acids [HPA, namely dodecatungstophosphoric acid [H3PO4.12WOa-xH2O] （TPA）, dodeca-molybdo phosphoric acid ammonium salt hydrate [H12Mo12N3040P＋aq] （DMAA）, sodium tungstate hydrated purified [Na12WO4.2H2O] （STH）] supported on clay, H-beta and TS-1. The 20%TPA/Clay, 30%TPA/H-Beta and 30%TPA/TS-1, were observed to be the best catalyst samples over plane clay, plane H-Beta and plane TS-1. The catalyst samples are compared with respect to benzyl chloride conversion and selectivities for diphenylmethane, dimethyl-diphenylmethane, benzyl toluene and benzoic acid. The reaction follows the pseudo-first order rate power law model. The apparent rate constants are calculated and compared with the reported ones.

关键词： toluene benzylation benzyl chloride heteropolyacid diphenylmethane dimethyl-diphenyl methane benzyl toluene benzoic acid

Coherent Bremsstrahlung at Beijing Electron-Positron Collider

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Chinese Physics Letters 1999年第8期16卷 557-559页

作者： DINg Yi-bing v.g.Serbo graduate School University of Science and Technology of China at BeijingChinese Academy of SciencesBeijing 1000393 Novosibirsk State University 630090 NovosibirskRussia Department of Physics University of MilanINFN20133 MilanItaly

The main characteristics of coherent bremsstrahlung (CBS) for the Beijing Electron-Positron Collider are calculated. At this collider dNγ~3 x 10^(8) dE_(γ)/E_(γ) photons of CBS will be emitted for a single collision of the beams in the energy range E_(γ)v. It seems that CBS can be a potential tool for optimizing collisions and measuring beam parameters. Indeed, the bunch length σz can be found from the CBS spectrum because critical energy Ec ∝ 1/σz;the horizontal transverse bunch size σx is related to dNγ∝1/σ^(2)_(x). In addition, CBS may be very useful for a fast control over an impact parameter R between the colliding bunch axes.

关键词： parameters. Electron coherent