Interpolation, Simple Elements, Convergence, Stress Calculation

1988 ◽  
pp. 71-119
Author(s):  
Robert D. Cook
Keyword(s):  
Stress Calculation

scholarly journals Equivalent Scalar Stress Formulation Taking into Account Non-Resolved Turbulent Scales

2021 ◽  
Author(s):  
Lucas Konnigk ◽  
Benjamin Torner ◽  
Martin Bruschewski ◽  
Sven Grundmann ◽  
Frank-Hendrik Wurm
Keyword(s):  
Mechanical Stress ◽  
Turbulence Models ◽  
Turbulent Channel Flow ◽  
Simulation Method ◽  
Blood Damage ◽  
Stress Calculation ◽  
High Risk Factors ◽  
Cardiovascular Engineering ◽  
Scalar Stress ◽  
Definition Of

Abstract Purpose Cardiovascular engineering includes flows with fluid-dynamical stresses as a parameter of interest. Mechanical stresses are high-risk factors for blood damage and can be assessed by computational fluid dynamics. By now, it is not described how to calculate an adequate scalar stress out of turbulent flow regimes when the whole share of turbulence is not resolved by the simulation method and how this impacts the stress calculation. Methods We conducted direct numerical simulations (DNS) of test cases (a turbulent channel flow and the FDA nozzle) in order to access all scales of flow movement. After validation of both DNS with literature und experimental data using magnetic resonance imaging, the mechanical stress is calculated as a baseline. Afterwards, same flows are calculated using state-of-the-art turbulence models. The stresses are computed for every result using our definition of an equivalent scalar stress, which includes the influence from respective turbulence model, by using the parameter dissipation. Afterwards, the results are compared with the baseline data. Results The results show a good agreement regarding the computed stress. Even when no turbulence is resolved by the simulation method, the results agree well with DNS data. When the influence of non-resolved motion is neglected in the stress calculation, it is underpredicted in all cases. Conclusion With the used scalar stress formulation, it is possible to include information about the turbulence of the flow into the mechanical stress calculation even when the used simulation method does not resolve any turbulence.

Collapse Reasons Analysis of a Large Steel Silo

2011 ◽  
Vol 368-373 ◽  
pp. 647-650
Author(s):  
Yue Dong Sun ◽  
Yan Pu Wang
Keyword(s):  
Temperature Stress ◽  
Critical Stability ◽  
Initial Imperfections ◽  
Stress Calculation ◽  
Large Steel ◽  
Pressure Calculation ◽  
Horizontal Pressure ◽  
Steel Silos ◽  
Design Factors ◽  
Discharge Method

Through the analysis of the collapse reasons of a large steel silo, results show that the main reasons for causing this accident are the design factors, containing horizontal pressure calculation, loads combination, critical stability stress calculation and so on. Temperature stress, storage mode and discharge method, initial imperfections of steel silos are the subordinate reasons and can not be ignored.

Robust Stress Check Formula of Lifting Padeye

2010 ◽  
Vol 54 (01) ◽  
pp. 34-40
Author(s):  
Zhou Bo ◽  
Liu Yujun ◽  
Ji Zhuoshang
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Accurate Method ◽  
Offshore Structures ◽  
Structure Design ◽  
Stress Calculation ◽  
Check Method ◽  
External Loads ◽  
Actual Stress ◽  
Element Method

Lifting padeyes are widely used in the construction of offshore structures and ships. It has been shown that the traditional check method cannot reflect the realistic value and distribution of actual stress on the padeyes. A more accurate method for the padeye stress calculation is essential and important for promoting the safety of the padeyes. In this paper, a new check formula is proposed based on the analysis of deformation and external loads distribution on lifting padeyes. The results of finite element method and the solutions of traditional check formula and new check formula are compared. It is shown that, by applying the stress check formula derived in the paper, the value and the location of the dangerous stresses occurred can be evaluated easily and exactly. The safe reliability of structure design can be improved significantly.

Transmission of Tension From a Bar to a Plate

1954 ◽  
Vol 21 (2) ◽  
pp. 147-150
Author(s):  
J. N. Goodier ◽  
C. S. Hsu
Keyword(s):  
Fatigue Strength ◽  
Strain Gage ◽  
Plane Stress ◽  
Fair Agreement ◽  
Lap Joint ◽  
Concentrated Force ◽  
Considerable Fraction ◽  
Stress Calculation ◽  
Local Character

Abstract When a bar or strip is lap-jointed to a plate, and transmits tension to it, the transmission is not effected only by a smooth distribution of force along the lap joint; there is also a highly concentrated force, a considerable fraction of the total tension, where the bar meets the plate, and a second force at the end of the bar. These forces are investigated by strain-gage measurements for various lengths of lap, and by a plane-stress calculation, with fair agreement. The results suggest that the fatigue strength of such joints will depend on the detailed local character of the joint where the bar meets the plate, rather than on the length of the joint.

Stress calculation in atomistic simulations of perfect and imperfect solids

2001 ◽  
Vol 89 (1) ◽  
pp. 99-104 ◽  
Author(s):  
J. Cormier ◽  
J. M. Rickman ◽  
T. J. Delph
Keyword(s):  
Atomistic Simulations ◽  
Stress Calculation

Numerical calculation of crack width in prestressed concrete beams with bond-slip effect

2019 ◽  
Vol 15 (2) ◽  
pp. 523-536
Author(s):  
Jinliang Liu ◽  
Yanmin Jia ◽  
Guanhua Zhang ◽  
Jiawei Wang
Keyword(s):  
Numerical Calculation ◽  
Numerical Model ◽  
Prestressed Concrete ◽  
Calculation Method ◽  
Crack Width ◽  
Calculation Model ◽  
Content Type ◽  
Bond Slip ◽  
Stress Calculation ◽  
Bonding Performance

Purpose The calculation of the crack width is necessary for the design of prestressed concrete (PC) members. The purpose of this paper is to develop a numerical model based on the bond-slip theory to calculate the crack width in PC beams. Design/methodology/approach Stress calculation method for common reinforcement after beam crack has occurred depends on the difference in the bonding performance between prestressed reinforcement and common reinforcement. A numerical calculation model for determining the crack width in PC beams is developed based on the bond-slip theory, and verified using experimental data. The calculation values obtained by the proposed numerical model and code formulas are compared, and the applicability of the numerical model is evaluated. Findings The theoretical analysis and experimental results verified that the crack width of PC members calculated based on the bond-slip theory in this study is reasonable. Furthermore, the stress calculation method for the common reinforcement is verified. Compared with the model calculation results obtained in this study, the results obtained from code formulas are more conservative. Originality/value The numerical calculation model for crack width proposed in this study can be used by engineers as a reference for calculating the crack width in PC beams to ensure the durability of the PC member.

scholarly journals A Novel Method for Tooth Bending Stress Calculation of Gears With Asymmetric Teeth

2021 ◽  
Author(s):  
Oguz DOGAN ◽  
Celalettin YUCE ◽  
Fatih KARPAT
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Experimental Studies ◽  
Element Model ◽  
Bending Stress ◽  
Element Analysis ◽  
Stress Calculation ◽  
Bending Stresses ◽  
New Equation ◽  
Asymmetric Factor

Abstract Today, gear designs with asymmetric tooth profiles offer essential solutions in reducing tooth root stresses of gears. Although numerical, analytical, and experimental studies are carried out to calculate the bending stresses in gears with asymmetric tooth profiles a standard or a simplified equation or empirical statement has not been encountered in the literature. In this study, a novel bending stress calculation procedure for gears with asymmetric tooth profiles is developed using both the DIN3990 standard and the finite element method. The bending stresses of gears with symmetrical profile were determined by the developed finite element model and was verified by comparing the results with the DIN 3990 standard. Using the verified finite element model, by changing the drive side pressure angle between 20° and 30° and the number of teeth between 18 and 100, 66 different cases were examined and the bending stresses in gears with asymmetric profile were determined. As a result of the analysis, a new asymmetric factor was derived. By adding the obtained asymmetric factor to the DIN 3390 formula, a new equation has been derived to be used in tooth bending stresses of gears with asymmetric profile. Thanks to this equation, designers will be able to calculate tooth bending stresses with high precision in gears with asymmetric tooth profile without the need for finite element analysis.

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