Stress calculation method for ring valve plates in compressors

1968 ◽  
Vol 4 (12) ◽  
pp. 980-982
Author(s):  
S. E. Narkunskii
Keyword(s):  
Calculation Method ◽  
Stress Calculation ◽  
Ring Valve

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.

A rapid stress calculation method for short flexspline harmonic drive

2019 ◽  
Vol 36 (6) ◽  
pp. 1852-1867 ◽  
Author(s):  
Shuang Wang ◽  
Gedong Jiang ◽  
Xuesong Mei ◽  
Chuang Zou ◽  
Xian Zhang ◽  
...  
Keyword(s):  
Finite Element ◽  
Calculation Method ◽  
Circumferential Stress ◽  
Element Model ◽  
Analytical Relationship ◽  
Analysis Method ◽  
Content Type ◽  
Stress Calculation ◽  
Mechanics Analysis ◽  
Rapid Calculation

Purpose Because of the compact structure, short flexspline (FS) harmonic drive (HD) is increasingly used. The stress calculation of FS is very important in design and optimization of HD system. This paper aims to study the stress calculation methods for short FS, based on mechanics analysis and finite element method (FEM). Design/methodology/approach A rapid stress calculation method, based on mechanics analysis, is proposed for the short FS of HD. To verify the stress calculation precision of short FS, a complete finite element model of HD is established. The results of stress and deformation of short FS in different lengths are solved by FEM. Findings Through the rapid calculation method, the analytical relationship between circumferential stress and length of cylinder was obtained. And the circumferential stress has proportional relation with the reciprocal of squared length. The FEM results verified that the rapid stress calculation method could obtain accurate results. Research limitations/implications The rapid mechanics analysis method is practiced to evaluate the strength of FS at the design stage of HD. And the complete model of HD could contribute to improving the accuracy of FEM results. Originality/value The rapid calculation method is developed based on mechanics analysis method of cylinder and equivalent additional bending moment model, through which the analytical relationship between circumferential stress and length of cylinder was obtained. The complete three-dimensional finite element model of HD takes the stiffness of bearing into consideration, which can be used in the numerical simulation in the future work to improve the accuracy.

scholarly journals Non-Hertzian Elastohydrodynamic Contact Stress Calculation of High-Speed Ball Screws

2021 ◽  
Vol 11 (24) ◽  
pp. 12081
Author(s):  
Tiewei Sun ◽  
Min Wang ◽  
Xiangsheng Gao ◽  
Yingjie Zhao
Keyword(s):  
Contact Stress ◽  
Calculation Method ◽  
High Speed ◽  
Contact Region ◽  
Friction Torque ◽  
Wear Depth ◽  
Asperity Contact ◽  
Stress Calculation ◽  
Elastohydrodynamic Contact ◽  
The Asymmetry

In order to eliminate the calculation error of the Hertzian elastohydrodynamic contact stress due to the asymmetry of the contact region of the helix raceway, a non-Hertzian elastohydrodynamic contact stress calculation method based on the minimum excess principle was proposed. Firstly, the normal contact stresses of the screw raceway and the nut raceway were calculated by the Hertzian contact theory and the minimum excess principle, respectively. Subsequently, the Hertzian solution and the non-Hertzian solution of the elastohydrodynamic contact stress could be determined by the Reynolds equation under different helix angles and screw speeds. Finally, the friction torque test of the double-nut ball screws was designed and implemented on a self-designed bed for validation of the proposed method. The comparison showed that the experimental friction torque was the good agreement with the simulated friction torque, which verified the effectiveness and correctness of the non-Hertzian elastohydrodynamic contact stress calculation method. Under the large helix angle, the calculation accuracy of asperity contact stress for the non-Hertzian solution was more accurate than that of the Hertzian solution at the contact region of ball screws. Therefore, the non-Hertzian elastohydrodynamic contact stress considering the asymmetry of the raceway contact region could more accurately analyze the wear depth of the high-speed ball screws.

Calculation of Stresses in Strained Semiconductor Layers

1994 ◽  
Vol 338 ◽  
Author(s):  
K. Nakajima
Keyword(s):  
Stress Distribution ◽  
Calculation Method ◽  
Thin Layers ◽  
Balance Method ◽  
Misfit Dislocations ◽  
Improved Method ◽  
Strained Layers ◽  
Stress Calculation ◽  
The Third

ABSTRACTA stress calculation method is proposed by improving the force and moment balance method to calculate the stress in semiconductor layers. The following three points are improved. The first point is that the vertically precise stress distribution in multilayers can be calculated by using imaginary thin layers. The second point is that the stress can be calculated on the basis of threedimensional deformation. The third point is that the stress can be calculated in strained layers with interfacial misfit dislocations. The stress distribution in strained semiconductor layers such as InGaAs/GaAs multilayers, InGaAs/graded lnGaAs/GaAs layers and GaAs/Si structures is calculated using this improved method.

scholarly journals A THERMAL STRESS CALCULATION METHOD OF CONCRETE PAVEMENT BASED ON TEMPERATURE PREDICTION AND FEM ANALYSIS

2016 ◽  
Vol 72 (3) ◽  
pp. I_105-I_113 ◽  
Author(s):  
Tatsuo NISHIZAWA ◽  
Masashi KOYANAGAWA ◽  
Yasushi TAKEUCHI ◽  
Kazuyuki KUBO ◽  
Toru YOSHIMOTO
Keyword(s):  
Thermal Stress ◽  
Calculation Method ◽  
Fem Analysis ◽  
Concrete Pavement ◽  
Temperature Prediction ◽  
Stress Calculation

scholarly journals Gear-Tooth Stress Calculation Method for Heavily Crowned Gear

1974 ◽  
Vol 17 (104) ◽  
pp. 264-272
Author(s):  
Komei FUJITA ◽  
Fumio OBATA ◽  
Kiichi MIYANISHI
Keyword(s):  
Calculation Method ◽  
Gear Tooth ◽  
Stress Calculation

Analysis of Bending Strength of the Rectangular Hole Honeycomb Beam

2013 ◽  
Vol 405-408 ◽  
pp. 993-996
Author(s):  
Su Juan Dai ◽  
Bao Chen Zhu ◽  
Qing Chen
Keyword(s):  
Mechanical Behavior ◽  
Normal Stress ◽  
Calculation Method ◽  
Bending Strength ◽  
Calculation Formula ◽  
Rectangular Hole ◽  
Stress Calculation ◽  
Behavior Based

This paper introduces the characteristics and practicability of the honeycomb beam and analyses the mechanical behavior. Based on the vierendeel truss theory, the normal stress calculation method of the rectangular hole honeycomb beam is discussed, and the calculation formula is deduced. Finally using the derived formula, the paper calculates the normal stress of the rectangular hole honeycomb beams with different parameters, and analyses the influence of the opening rate and the hole spacing on the strength of honeycomb beam by comparing the same section of solid web beam, thus, provides reference for design of steel honeycomb beam.

scholarly journals Stress calculation method of bending multilayer structural element when bending moment acts in the planes that do not coincident with principal planes

2021 ◽  
Vol 47 ◽  
Author(s):  
Vytautas Kleiza ◽  
Jonas Kleiza
Keyword(s):  
Normal Stress ◽  
Cross Section ◽  
Calculation Method ◽  
Bending Moment ◽  
Beam Cross Section ◽  
Structural Element ◽  
Stress Calculation ◽  
Multilayer Beam ◽  
Principal Axes ◽  
Multilayer Beams

This paper presents stress calculationmethod of bending multilayer structural element when bending moment acts in the planes that do not coincident with principal planes, and cross section is symmetric or asymmetric. Carrying the computation of occurring stress values in multilayer beam layers it is necessary to identify coordinates of cross-section stiffness centre, direction of principal axes, and coordinates of specific points regarding principal axes. Having this information and equation which is valid for stress calculation of bending multilayer beams it is possible to identify normal stress values at any point of the beam cross section under skew bending. It is deduced that stress values and the nature of their changes are influenced by the shape of beam cross-section, its asymmetry degree, and the direction of appliedmoment.

scholarly journals Fatigue Models for Airfield Concrete Pavement: Literature Review and Discussion

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6579
Author(s):  
Jie Yuan ◽  
Wenhao Li ◽  
Yuening Li ◽  
Lukuan Ma ◽  
Jiake Zhang
Keyword(s):  
Regression Analysis ◽  
Literature Review ◽  
Calculation Method ◽  
Concrete Pavement ◽  
Civil Aviation ◽  
Wheel Load ◽  
Stress Calculation ◽  
Analysis Process ◽  
Fatigue Model ◽  
Data Source

The fatigue model plays an important role in the mechanistic–empirical design procedure of airfield pavement. As for cement concrete pavement, the fatigue model represents the relationship between the stress and the number of load repetitions. To further understand the fatigue model, a literature review was performed in this paper along with the discussion. In this paper, the developed fatigue models available now were classified as the full-scale testing-based fatigue model and the concrete beam testing-based fatigue model, according to the data source. Then, the regression analysis process and stress calculation method of each fatigue model were summarized. Besides, the fatigue model proposed by the Federal Aviation Administration (FAA) was compared with the fatigue model of the Civil Aviation Administration of China (CAAC). The design thicknesses using the two models were obtained based on the finite element analysis. The results show that the designed slab using the fatigue model of FAA is thicker than that of CAAC, meaning that the fatigue model of FAA is comparatively conservative. Moreover, it can be concluded that the differences in the slab thickness become more significant with the increase in the wheel load and the foundation strength. Finally, the recommendation was proposed to refine the fatigue model in the future study from three aspects: data source, stress calculation method, and regression analysis process.

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