Numerical study of stress distribution in sheared granular material in two dimensions

Purpose The purpose of this paper is to carry out a numerical study on the dynamic and thermal behavior of a fluid with a constant property and flowing turbulently through a two-dimensional horizontal rectangular channel. The upper surface was put in a constant temperature condition, while the lower one was thermally insulated. Two transverse, solid-type obstacles, having different shapes, i.e. flat rectangular and V-shaped, were inserted into the channel and fixed to the top and bottom walls of the channel, in a periodically staggered manner to force vortices to improve the mixing, and consequently the heat transfer. The flat rectangular obstacle was put in the first position and was placed on the hot top wall of the channel. However, the second V-shaped obstacle was placed on the insulated bottom wall, at an attack angle of 45°; its position was varied to find the optimum configuration for optimal heat transfer. Design/methodology/approach The fluid is considered Newtonian, incompressible with constant properties. The Reynolds averaged Navier–Stokes equations, along with the standard k-epsilon turbulence model and the energy equation, are used to control the channel flow model. The finite volume method is used to integrate all the equations in two-dimensions; the commercial CFD software FLUENT along with the SIMPLE-algorithm is used for pressure-velocity coupling. Various values of the Reynolds number and obstacle spacing were selected to perform the numerical runs, using air as the working medium. Findings The channel containing the flat fin and the 45° V-shaped baffle with a large Reynolds number gave higher heat transfer and friction loss than the one with a smaller Reynolds number. Also, short separation distances between obstacles provided higher values of the ratios Nu/Nu0 and f/f0 and a larger thermal enhancement factor (TEF) than do larger distances. Originality/value This is an original work, as it uses a novel method for the improvement of heat transfer in completely new flow geometry.

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Destabilization of Immersed Dense Granular Material Submitted to Localized Fluidization: An Experimental and Numerical Study

Journal of Spectroscopy ◽

10.1155/2021/5542835 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Aboubacar Sidiki Dramé ◽

Li Wang ◽

Yanping Zhang

Keyword(s):

Granular Material ◽

Granular Medium ◽

Experimental Approach ◽

Solid Phase ◽

Numerical Study ◽

Lighting System ◽

Led Lighting ◽

Hydrogel Beads ◽

Static Regime ◽

As Solid Phase

An alternative experimental approach and a numerical analysis for the study of destabilization by localized fluidization of an immersed dense granular material are presented. To visualize the evolutions of the internal structure of the granular medium, the hydrogel beads, composed of about 99% of water and having substantially the same refraction indexes, are used as solid phase. A LED lighting system is used in place of a laser lighting system. As a result, the optical access restriction of porous structure is removed. A real economic alternative for the experimental study of fluid-grain coupling during destabilization by localized fluidization of a granular material is created. The experimental phenomenology presented in the literature is verified: the system passes successively through three different stationary regimes: static regime, fluidized cavity regime, and fluidized chimney regime. Some restrictions of using hydrogel beads as particles in the study of liquid-solid interaction are also discussed.

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Numerical Study of the Shear Stress Distribution in an I-Beam in the Load Application Zone

Materials Science Forum ◽

10.4028/www.scientific.net/msf.974.659 ◽

2019 ◽

Vol 974 ◽

pp. 659-664 ◽

Cited By ~ 1

Author(s):

Sergey Saiyan ◽

Alexander Paushkin

Keyword(s):

Shear Stress ◽

Stress Distribution ◽

Software Package ◽

Numerical Study ◽

Shear Stress Distribution ◽

Load Application ◽

Tangential Stresses

A study on the Saint-Venant principle implementation for a rigidly clamped I-beam loaded with various loads at the free end was carried out. When using the software package LIRA SAPR, the tangential stresses perturbations zones are determined in order to compare their distribution with the materials resistance solution.

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Experimental and numerical study of residual stress distribution of corrugated web I-beams

Journal of Constructional Steel Research ◽

10.1016/j.jcsr.2019.105926 ◽

2020 ◽

Vol 166 ◽

pp. 105926

Author(s):

Zhi-Yu Wang ◽

Tao Zhang ◽

Xiaolei Li

Keyword(s):

Residual Stress ◽

Stress Distribution ◽

Numerical Study ◽

Residual Stress Distribution ◽

Corrugated Web

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A numerical study of the interaction between two ejecta in the interplanetary medium: one- and two-dimensional hydrodynamic simulations

Annales Geophysicae ◽

10.5194/angeo-22-3741-2004 ◽

2004 ◽

Vol 22 (10) ◽

pp. 3741-3749 ◽

Cited By ~ 16

Author(s):

A. Gonzalez-Esparza ◽

A. Santillán ◽

J. Ferrer

Keyword(s):

Hydrodynamic Model ◽

Physical Mechanism ◽

Interplanetary Medium ◽

Numerical Study ◽

Two Dimensions ◽

Magnetic Clouds ◽

The Sun ◽

Two Dimensional ◽

Hydrodynamic Simulations

Abstract. We studied the heliospheric evolution in one and two dimensions of the interaction between two ejecta-like disturbances beyond the critical point: a faster ejecta 2 overtaking a previously launched slower ejecta 1. The study is based on a hydrodynamic model using the ZEUS-3-D code. This model can be applied to those cases where the interaction occurs far away from the Sun and there is no merging (magnetic reconnection) between the two ejecta. The simulation shows that when the faster ejecta 2 overtakes ejecta 1 there is an interchange of momentum between the two ejecta, where the leading ejecta 1 accelerates and the tracking ejecta 2 decelerates. Both ejecta tend to arrive at 1AU having similar speeds, but with the front of ejecta 1 propagating faster than the front of ejecta 2. The momentum is transferred from ejecta 2 to ejecta 1 when the shock initially driven by ejecta 2 passes through ejecta 1. Eventually the two shock waves driven by the two ejecta merge together into a single stronger shock. The 2-D simulation shows that the evolution of the interaction can be very complex and there are very different signatures of the same event at different viewing angles; however, the transferring of momentum between the two ejecta follows the same physical mechanism described above. These results are in qualitative agreement with in-situ plasma observations of "multiple magnetic clouds" detected at 1AU.

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FE Modeling of Stress Distribution in MAO Coating on TC4 Substrate under Thermal Shock Cyclic Loading

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.941-944.1629 ◽

2014 ◽

Vol 941-944 ◽

pp. 1629-1632 ◽

Cited By ~ 1

Author(s):

Ye Sheng Zhong ◽

Li Ping Shi ◽

Ming Wei Li ◽

Jia Yu ◽

Jian Han Liang ◽

...

Keyword(s):

Shear Stress ◽

Thermal Stress ◽

Stress Distribution ◽

Adhesive Strength ◽

Thermal Cycle ◽

Radial Stress ◽

Numerical Study ◽

Element Analysis ◽

Solid Element ◽

Cycle Loading

A numerical study using finite element analysis (FEA) was performed to investigate the thermal, shear and radial stresses developed in MAO coating on substrate of TC4 under thermal cycle loading. The four-node quadrilateral thermal solid element PLANE55 and four-node quadrilateral structural solid element PLANE42 with axisymmetric option was used to model the temperature distribution and thermal stress field of the MAO coating on TC4 substrates. The thermal stress, radial stress and shear stress along the thickness in film/substrate system are analyzed systematically under different thermal cycle loading. It is found that the thermal stress of MAO coating exhibits a linear relationship with thickness of substrate, but it exhibit a parabolic relationship with the thickness of the coating. The radial stress and shear stress distribution of the coating–substrate combination are also calculated. It is observed that high tensile shear stress of MAO coating on TC4 substrate reduces its adhesive strength but high-compressive shear stress improves its adhesive strength.

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Numerical Study of Liquid Core Solidification in Influence of Soft Reduction Deformation on Steel Slab Continuous Casting Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.575-578.80 ◽

2008 ◽

Vol 575-578 ◽

pp. 80-86 ◽

Cited By ~ 3

Author(s):

J. Luo ◽

Xin Lin ◽

Yan Hong Ye ◽

K.W. Liu

Keyword(s):

Continuous Casting ◽

Numerical Study ◽

Liquid Core ◽

Solidification Process ◽

Casting Process ◽

Reduction Factor ◽

Two Dimensions ◽

Temperature Function ◽

Soft Reduction ◽

Steel Slab

A two dimensions (2D) multiphase solidification model is used to study the liquid core solidification in the influence of deformation during soft reduction of continuous casting (CC). The transient transport equations (mass, momentum and enthalpy) for each phase of a thin steel slab CC are solved. Four different cases including of density-temperature function and deformation reduction factor on this CC are simulated. The solidification ending point position of liquid core, temperature, velocity and fracture of liquid and solid phases are compared. Understandings to the deformation and liquid core formation mechanism on soft reduction solidification process of CC are improved.

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