Impact of Environment Temperature Reduction on Force Performance of Steel Silos

2012 ◽  
Vol 204-208 ◽  
pp. 917-920
Author(s):  
Yue Dong Sun ◽  
Yan Pu Wang
Keyword(s):  
Axial Stress ◽  
Circumferential Stress ◽  
Stress Increase ◽  
Temperature Reduction ◽  
Environment Temperature ◽  
Cold Area ◽  
Steel Silos ◽  
The Impact

Based on the engineering case of a steel silo used for storage cement, the circumferential stress and axial stress of steel silo wall was carried out by ANSYS, when environment temperature falls. Result shows that the impact of environment temperature reduction on the silo wall circumferential stress is significant while the impact on axial stress is small. Circumferential stress increase about 21MPa and axial stress increase 4.1MPa when the environment temperature falls 10°C.The impact of temperature reduction should be taking into account in the design of steel silos in cold area.

scholarly journals Thermoelastic analysis of FGM hollow cylinder for variable parameters and temperature distributions using FEM

2020 ◽  
Vol 9 (1) ◽  
pp. 256-264
Author(s):  
Dinkar Sharma ◽  
Ramandeep Kaur
Keyword(s):  
Stress Field ◽  
Hollow Cylinder ◽  
Numerical Study ◽  
Axial Stress ◽  
Circumferential Stress ◽  
Functionally Graded ◽  
Gradient Index ◽  
Variable Parameters ◽  
Graded Material ◽  
Governing Differential Equation

AbstractThis paper presents, numerical study of stress field in functionally graded material (FGM) hollow cylinder by using finite element method (FEM). The FGM cylinder is subjected to internal pressure and uniform heat generation. Thermoelastic material properties of FGM cylinder are assumed to vary along radius of cylinder as an exponential function of radius. The governing differential equation is solved numerically by FEM for isotropic and anistropic hollow cylinder. Additionally, the effect of material gradient index (β) on normalized radial stresses, normalized circumferential stress and normalized axial stress are evaluated and shown graphically. The behaviour of stress versus normalized radius of cylinder is plotted for different values of Poisson’s ratio and temperature. The graphical results shown that stress field in FGM cylinder is influenced by some of above mentioned parameters.

X-ray residual stress analysis of cylindrically curved surfaces—estimation of circumferential distributions of residual stresses

2003 ◽  
Vol 38 (5) ◽  
pp. 459-468 ◽  
Author(s):  
T Oguri ◽  
K Murata ◽  
Y Sato
Keyword(s):  
Residual Stresses ◽  
Least Squares Method ◽  
Stress Measurement ◽  
Incident Angle ◽  
Axial Stress ◽  
Circumferential Stress ◽  
Distribution Functions ◽  
Scanning Method ◽  
X Ray ◽  
Reference Axis

A new measuring technique utilizing X-ray diffraction is proposed in order to estimate the circumferential distributions of residual stresses on convex/concave cylindrical surfaces. This technique requires neither tilting X-ray beams in the circumferential direction in which the X-ray incident angle tends to be limited nor adjusting the normal of the irradiation area to the reference axis of the ψ angle. The circumferential distributions of the circumferential stress and of the axial stress are estimated from the diffraction angles at ψ = 0° and the axial stresses obtained by the stress measurement on multiple inclined areas on the cylindrical surfaces under the configuration of the axial stress measurement using the iso-inclination scanning method. This estimate technique was applied to two round bars of steel, one with circumferential distributions of the residual stresses and the other with almost uniform stresses. The distribution functions of the residual stresses were expanded to a couple of Fourier series, and the coefficients of them were determined by the least-squares method. The estimated distributions of the residual stresses were in good agreement with the actual ones.

Finite Element Analysis of Creep Behavior of AZ91D Magnesium Matrix Composites Reinforced with Aluminum Silicate Short Fibers

2012 ◽  
Vol 568 ◽  
pp. 311-314
Author(s):  
Jun Tian ◽  
Shou Yan Zhong ◽  
Zi Qiong Shi
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Creep Rate ◽  
Creep Behavior ◽  
Axial Stress ◽  
Short Fiber ◽  
Steady Creep ◽  
Element Analysis ◽  
Interface Module ◽  
The Impact

By Computer finite element analysis, the impact of the interface thickness, the interface module and the short fiber orientation of Al2O3-SiO2(sf)/AZ91D composite on the maximum fiber axial stress and the steady creep rate is studied. Maximum axial stress of the short fiber is in the fiber center, and the axial stress gradually decreases along the direction of the fiber length. When the external stress is constant, the maximum fiber axial stress increases with decreasing of the thickness of the interface, and the steady creep rate increases with the increasing of thickness of the interface. The maximum fiber axial stress increases with the increasing of the interface modulus, the increasing of the interface module improves the load transfer and the creep resistance. Finite element simulation results and experimental results can be well matched to better explain the creep behavior.

scholarly journals Application of Potassium Ion Deposition in Determining the Impact of Support Reducibility on Catalytic Activity of Au/Ceria-Zirconia Catalysts in CO Oxidation, NO Oxidation, and C3H8 Combustion

Catalysts ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 688
Author(s):  
Ewa M. Iwanek (nee Wilczkowska) ◽  
Leonarda F. Liotta ◽  
Shazam Williams ◽  
Linjie Hu ◽  
Krishelle Calilung ◽  
...  
Keyword(s):  
Low Temperature ◽  
Co Oxidation ◽  
Gold Catalysts ◽  
Maximum Temperature ◽  
Potassium Ions ◽  
Reduction Peak ◽  
Temperature Reduction ◽  
Potassium Loading ◽  
The Impact ◽  
Low Temperature Reduction

The purpose of the study was to show how a controlled, subtle change of the reducibility of the support by deposition of potassium ions impacts the activity of gold catalysts. Since the activity of supported gold catalysts in carbon monoxide oxidation is known to strongly depend on the reducibility of the support, this reaction was chosen as the model reaction. The results of tests conducted in a simple system in which the only reagents were CO and O2 showed good agreement with the CO activity trend in tests performed in a complex stream of reagents, which also contained CH4, C2H6, C3H8, NO, and water vapor. The results of the X-ray Diffraction (XRD) studies revealed that the support has the composition Ce0.85Zr0.15O2, that its lattice constant is the same for all samples, and that gold is mostly present in the metallic phase. The reducibility of the systems was established based on Temperature Programmed Reduction (TPR) and in situ XRD measurements in H2 atmosphere. The results show that the low temperature reduction peak, which is due to the presence of gold, is shifted to a higher value by the presence of 0.3 at% potassium ions on the surface. Moreover, the increase of the potassium loading leads to a more pronounced shift. The T50 of CO oxidation in the simple model stream was found to exhibit an excellent linear correlation with the maximum temperature of the low temperature reduction peak of Au catalysts. This means that stabilizing oxygen with a known amount of potassium ions can be numerically used to estimate the T50 in CO oxidation. The results in the complex stream also showed a similar dependence of CO conversion on reducibility, though there was no substantial difference in the activity of the catalysts in other reactions regardless of the potassium loading. These studies have shown that the influence of potassium varies depending on the reaction, which highlights differences in the impact of reducibility and importance of other factors in these reactions.

Effect of Critical Void Volume Fraction fF on Results of Ductile Fracture Simulation for S235JR Steel under Multi-Axial Stress States

2014 ◽  
Vol 598 ◽  
pp. 113-118 ◽  
Author(s):  
Paweł Grzegorz Kossakowski ◽  
Wiktor Wciślik
Keyword(s):  
Volume Fraction ◽  
Axial Stress ◽  
Material Model ◽  
Model Parameters ◽  
Material Microstructure ◽  
Fracture Simulation ◽  
Critical Volume Fraction ◽  
Stress States ◽  
The Impact ◽  
Critical Void

The article describes an example of the GTN material model parameters determination and application. The main objective of the study was to determine experimentally the value of the critical volume fraction of voids fFfor S235JR steel and to assess the impact of this parameter on the numerical force-elongation curve under the multi-axial stress state. Value of fFwas obtained by the quantitative analysis of the material microstructure at fracture surfaces. For a sake of comparison, two other values of fF, described in the literature, were also used in numerical simulations.

Haze Formation and the Influence of Ethanol Gasoline of Severe Cold Area on Haze

2014 ◽  
Vol 665 ◽  
pp. 528-533
Author(s):  
Li Bai ◽  
Wen Tao Chang
Keyword(s):  
Particulate Matter ◽  
Formation Mechanism ◽  
Aerosol Particles ◽  
Combustion Products ◽  
Cold Winter ◽  
Aldehydes And Ketones ◽  
Cold Area ◽  
Regional Haze ◽  
Haze Formation ◽  
The Impact

By analyzing the composition of haze and its formation mechanism, this thesis studies the impact of ethanol gasoline combustion products: aerosol particles, particulate matter, additional products (aldehydes and ketones, etc.) and water on severe cold area regional haze formation. The results show that the effect of ethanol gasoline combustion products on haze formation is also very serious. Therefore, this article does not recommend excessive use of ethanol gasoline in the cold winter.

Experimental Studies on the Impact Buckling of Bars and the Effect of Stress Wave

2006 ◽  
Vol 326-328 ◽  
pp. 1621-1624
Author(s):  
Rui Wang ◽  
Zhi Jun Han ◽  
Shan Yuan Zhang
Keyword(s):  
Stress Wave ◽  
Axial Stress ◽  
Axial Strain ◽  
Experimental Studies ◽  
Time History ◽  
Dynamic Buckling ◽  
Buckling Load ◽  
Quantitative Relation ◽  
Lateral Velocity ◽  
The Impact

The experimental studies on the dynamic buckling of the perfect bars with three kinds of lengths under impulsive axial compression were completed and the boundary condition of clamped-fixed was realized firstly in present studies. The time-history curves of axial strain of bars under different impact velocity were recorded. According to the magnitudes of the axial strain and bifurcate time, the quantitative relation of dynamic buckling load and critical bifurcate length are achieved; according to the curves recorded, the lateral velocity of bars are computed also. The experimental results show that the dynamic buckling load of the bar is distinctly greater than the static one, the front of stress wave can be regarded as fixed and the effect of the axial stress wave in the dynamic buckling of bar must be considered.

Stress and Strain Distribution in Hypertensive and Normotensive Rat Aorta Considering Residual Strain

1996 ◽  
Vol 118 (1) ◽  
pp. 62-73 ◽  
Author(s):  
Takeo Matsumoto ◽  
Kozaburo Hayashi
Keyword(s):  
Residual Stresses ◽  
Wall Thickness ◽  
Axial Stress ◽  
Circumferential Stress ◽  
Circumferential Direction ◽  
Wall Thickening ◽  
Left Renal Artery ◽  
Stress And Strain ◽  
Stress Distributions ◽  
Cross Sectional

The effects of hypertension on the stress and strain distributions through the wall thickness were studied in the rat thoracic aorta. Goldblatt hypertension was induced by constricting the left renal artery for 8 weeks. Static pressure-diameter-axial force relations were determined on excised tubular segments. The segments were then sliced into thin ring specimens. Circumferential strain distributions were determined from the cross-sectional shape of the ring specimens observed before and after releasing residual stresses by radial cutting. Stress distributions were calculated using a logarithmic type of strain energy density function. The wall thickness at the systolic blood pressure, Psys, significantly correlated with Psys. The mean stress and strain developed by Psys in the circumferential direction were not significantly different between the hypertensive and control aortas, while those in the axial direction were significantly smaller in the hypertensive aorta than in the control. The opening angles of the stress-free ring specimens correlated well with Psys. The stress concentration factor in the circumferential direction was almost constant and independent of Psys, although the stress distributions were not uniform through the wall thickness. Histological observation showed that the wall thickening caused by hypertension is mainly due to the hypertrophy of the lamellar units of the media, especially in the subintimal layer where the stress increase developed by hypertension is larger than in the other layers. These results indicate that: (a) the aortic wall adapts itself to the mechanical field by changing not only the wall dimensions but also the residual stresses, (b) this adaptation is primarily related to the circumferential stress but not to the axial stress, and (c) the aortic smooth muscle cells seem to change their morphology in response to the mechanical stress.

scholarly journals Influence of Cyclic Impact Loading and Axial Stress on Dynamic Mechanical Properties of Burst-Prone Coal

2021 ◽  
Vol 2021 ◽  
pp. 1-10 ◽  
Author(s):  
Shuang Gong ◽  
Zhen Wang ◽  
Lei Zhou ◽  
Wen Wang
Keyword(s):  
Mechanical Properties ◽  
Impact Loading ◽  
Coal Sample ◽  
Impact Load ◽  
Axial Stress ◽  
Dynamic Mechanical Properties ◽  
Dynamic Mechanical ◽  
Cyclic Impact Loading ◽  
Cyclic Impact ◽  
The Impact

High in-situ stress and frequent dynamic disturbances caused by the mining process in deep coal mines can easily induce dynamic disasters such as coal burst. We conducted laboratory experiments to assess the effects of the axial stress loading and dynamic cyclic impact loading on the dynamic mechanical properties of burst-prone coals by using a modified split Hopkinson pressure bar (SHPB). Comparisons were made using two types of burst-prone and burst-resistant coal samples. The mineral components, organic macerals, and dynamic mechanical features of both burst-prone and burst-resistant coal samples were comparatively analyzed based on the obtained X-ray diffraction (XRD), optical microscope observations, and dynamic compressive stress-strain curves, respectively. The results of the microstructure analysis indicated a larger difference between the minimum and maximum reflectances of vitrinite for burst-prone coal. Compared to the burst-resistant coal samples, the burst-prone coals contained less corpocollinite and fusinite. While applying a high axial static load combined with cyclic impact load, the coal samples showed the characteristics of fatigue damage. The results also demonstrated that preaxial stress affected the burst resistance of coal samples. The greater the preaxial stress was, the less the coal samples could withstand the dynamic cyclic impact load. In comparison to the burst-resistant coal sample, the burst-prone coal sample showed a larger dynamic compressive strength and a lower deformation. They were also more positively capable of the propagation and activation of the coal burst. We believe that the results of the study are conducive to further understanding of the distribution of microcomponents of burst-prone coals. The results are also beneficial for realizing the dynamic mechanical characteristics of burst-prone coals under the impact of cyclic dynamic load.

scholarly journals Deformation Mechanism Analysis of Three-Roller Continuous and Synchronous Calibration Process of Straightness and Roundness For LSAW Pipes

2021 ◽  
Author(s):  
Xueying Huang ◽  
Gaochao Yu ◽  
Chunge Wang ◽  
Jun Zhao
Keyword(s):  
Deformation Mechanism ◽  
Axial Stress ◽  
Circumferential Stress ◽  
Mechanism Analysis ◽  
Calibration Process ◽  
Theoretical Support ◽  
Bending Process ◽  
Axial Curvature ◽  
The Difference ◽  
Submerged Arc

Abstract Continuous and synchronous calibration process of straightness and roundness for LSAW (Longitudinally Submerged Arc Welding, LSAW) pipes with three rollers is a bidirectional reciprocating bending process that includes axial and circumferential directions. It is particularly important to reveal the deformation mechanism, which provides theoretical support for the calibration process to be applied to actual production. Based on this, through the combination of references, theoretical analysis and numerical simulation, the deformation mechanism is analyzed in this paper. The whole deformation process of pipe is modeled and then numerically simulated with FEM software of ABAQUS. The results show that reciprocating bending can eliminate the difference of initial curvature, so that the axial curvature and circumferential curvature are unified to the same direction and value respectively. The synergy between the axial reciprocating bending straightening process and the circumferential reciprocating bending rounding process realizes the calibration process of LSAW pipes. The simulation results support the theoretical results, and the deformation is mainly caused by axial stress and circumferential stress.

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