Numerical Study on Shear Stress Variation of RC Wall with L Shaped Section

In a suspension culture of iPS cells, the shear stress generated during mixing is expected to promote differentiation of induced pluripotent stem (iPS) cells. The stress on the cells can be controlled by rotational rate and shape of impeller. However, it is difficult to optimize these operative parameters by experiments. Therefore, we have developed a numerical model to obtain the average and the maximum shear stress in two kinds of stirred tanks and an orbital shaking cylindrical container. The present results showed that the shear stress strongly depended on the type of mixing and lesser extent on the shape of the impeller. The average shear stress is larger in the shaking mode than that in the stirring mode. In contrast, the maximum shear stress is much smaller in the shaking than the stirring. These results suggest that stirring and shaking should be selectively used depending on the application

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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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Mechanism of Chip Segmentation in Orthogonal Cutting of Zr-Based Bulk Metallic Glass

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4043837 ◽

2019 ◽

Vol 141 (8) ◽

Cited By ~ 4

Author(s):

Naresh Kumar Maroju ◽

Xiaoliang Jin

Keyword(s):

Shear Stress ◽

Large Strain ◽

Orthogonal Cutting ◽

Amorphous Structure ◽

Experimental Result ◽

Thermomechanical Model ◽

Stress Variation ◽

Highly Sensitive ◽

Shear Transformation ◽

Shear Transformation Zones

Abstract Bulk metallic glasses (BMGs) are a series of metal alloys with an amorphous structure. The deformation of BMGs occurs in localized regions and is highly sensitive to the applied stress, strain rate, and temperature. This paper presents a coupled thermomechanical model to analyze the chip segmentation mechanism due to material shear localization in orthogonal cutting of Zr-BMG. The shear stress variation in the primary shear zone is modeled considering the tool-chip friction and large strain of the material. The constitutive property of BMG corresponding to the inhomogeneous deformation through shear transformation zones is modeled. The oscillations of shear stress, temperature, and free volume are simulated based on the cutting conditions. The predicted chip segmentation frequency is compared with the experimental result under different cutting speeds and uncut chip thicknesses. The developed model provides the fundamental mechanism of material deformation and chip formation in cutting Zr-BMG with an amorphous structure.

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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 Impingement and Film Composite Cooling on Blade Leading Edge

Volume 5A: Heat Transfer ◽

10.1115/gt2014-26643 ◽

2014 ◽

Cited By ~ 1

Author(s):

Zhao Liu ◽

Lv Ye ◽

Zhenping Feng

Keyword(s):

Shear Stress ◽

Nusselt Number ◽

Numerical Study ◽

Density Ratio ◽

Leading Edge ◽

Cooling Effectiveness ◽

Simulation Accuracy ◽

Film Composite ◽

Blowing Ratio ◽

Shear Stress Transport

In this paper a numerical study is performed to simulate the impingement and film composite cooling on the first stage rotor blade of GE-E3 engine high pressure turbine. A commercial CFD software CFX11.0 with a 3D RANS approach is adopted in the study. Firstly, by comparing with available experimental data, the relative performance of four turbulence models for numerical impingement and film composite cooling is studied, including the standard k-ε model, the RNG k-ε model, the standard k-ω model and the Shear-Stress Transport k-ω model. The Shear-Stress Transport k-ω model is chosen for the numerical study as it shows the best simulation accuracy. Then the simulations consist of five different density ratios (1.16∼4.81) and seven different blowing ratios (0.5∼3.0). The results indicate that the cooling effectiveness on pressure side is lower than that on the suction side. The cooling effectiveness increases with the increase of blowing ratio in the study range, but decreases with the increase of density ratio. On the target surface, the average Nusselt number, the circumferential averaged Nusselt number and its peak value increase with the increasing in blowing ratio, but decrease with the increase of density ratio.

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Numerical Study on Diastolic Left Ventricular Hemodynamics Using Motion Models of Mitral Valve With/Without Edge-to-Edge Repair

ASME 2010 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2010-19570 ◽

2010 ◽

Author(s):

Yingying Hu ◽

Liang Shi ◽

Siva Parameswaran ◽

Sergey A. Smirnov ◽

Zhaoming He

Keyword(s):

Shear Stress ◽

Mitral Valve ◽

Left Ventricle ◽

Platelet Activation ◽

Numerical Study ◽

Left Ventricular ◽

High Shear ◽

High Shear Stress ◽

Orifice Area ◽

Motion Models

Edge-to-edge repair (ETER) is a newly developed technique to correct such mitral valve (MV) malfunctions as regurgitation [1,2]. This technique changes MV geometric configuration by suturing the anterior and posterior leaflets at central or commissural edges, and consequently alters MV and left ventricle (LV) dynamics. For instance, stress in the MV elevated due to ETER may cause leaflets tearing near suture. Little has been known about shear stress on the MV and LV walls under MV ETER conditions, where high shear stress might cause platelet activation or hemolysis [3]. When ETER is done at the central leaflet edges, it generates two MV orifices, leads to two deflected jets, and completely changes vortices in the LV. ETER also reduces the orifice area, and increases jet velocity and transmitral pressure [1,2,4]. Flow patterns in the LV and ETER effects on the LV and MV functions have not been understood well.

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Finite Element and Experimental Studies of Creep at the Interface of Press Fitted Gears-Shafts Connections

Journal of Mechanical Design ◽

10.1115/1.2826930 ◽

1996 ◽

Vol 118 (4) ◽

pp. 568-572 ◽

Cited By ~ 1

Author(s):

N. Okamoto ◽

N. Tanaka ◽

M. Nogami

Keyword(s):

Finite Element ◽

Shear Stress ◽

Theoretical Calculations ◽

Experimental Studies ◽

Numerical Results ◽

Frictional Torque ◽

Slip Model ◽

Relative Movement ◽

Stress Variation ◽

Shrink Fit

It is shown experimentally that relative movement of shrink-fit connections occurs on mating surfaces even if the transmitting torque does not exceed the static frictional torque. However, there is a transmitting torque threshold below which no relative movement occurs. The experimental thresholds agree well with predictions from theoretical calculations of the slip model, which is based on the numerical results of shear stress variation along the interface and on Coulomb’s law of friction.

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