Use of the finite-element method to study the temperature-stress state of pistons in internal-combustion engines

Thin-walled structures may contain defects as cracks and holes that are leftovers of the material the construction, is made of or they occur during the operation as a result of, for example, mechanical damage. The presence of holes in the plate causes a concentration of stresses at the boundary of the holes and ultimately leads to premature failure of the structural element. Repair of local damage of modern aircraft structures can be made by creating overlays that are glued to the main structure. The overlay takes on part of the load, unloading the damaged area. This method of repair provides tightness and aerodynamic efficiency to the structure. The calculation of the stress state of such glued structures is usually performed by using the finite element method. The classic models of the stress state of overlapped joints are one-dimensional. That is, the change of the stress state along only one coordinate is considered. At the same time, the connections of a rectangular form are also considered. The purpose of this work is to create a mathematical model of the stress state of circular axisymmetric adhesive joints and to build an appropriate analytical solution to the problem. It is assumed that the bending of the plates is absent; the deformation of the plates is even by thickness. The adhesive layer works only on the shift. The main plate and the overlay are considered isotropic. The solution is built on polar coordinates. The stress state of the connection depends only on the radial coordinate, i.e. one-dimensional. The solution is obtained in analytical form. This mathematical model is a generalization of the classical model of the adhesive connection of Volkersen to a circular or annular region and is considered for the first time. Boundary conditions are met exactly. The satisfaction of marginal conditions, as well as boundary conditions, leads to a system of linear equations with respect to the unknown coefficients of the obtained solutions. The model problem is solved and the numerical results are compared with the results of calculations performed by using the finite element method. It is shown that the proposed model has sufficient accuracy for engineering problems and can be used to solve problems of the design of aerospace structures.

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Investigation of stability of cylindrical shells in inhomogeneous stress state by the finite-element method

Soviet Applied Mechanics ◽

10.1007/bf00884514 ◽

1978 ◽

Vol 14 (3) ◽

pp. 258-264

Author(s):

V. V. Kabanov ◽

L. P. Zheleznov

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Stress State ◽

Cylindrical Shells ◽

The Finite Element Method ◽

Element Method

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The Action Result of the Concentrated Load on the Briquettes which Obtained from the Technogenous Material

KnE Materials Science ◽

10.18502/kms.v2i2.953 ◽

2017 ◽

Vol 2 (2) ◽

pp. 97

Author(s):

Yu.N. Loginov ◽

N.А. Babailov ◽

D.N. Pervukhina

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Stress State ◽

The Finite Element Method ◽

Concentrated Load ◽

Tensile Stresses ◽

Calculation Results ◽

Element Method

<p class="TTPAbstract">In this study, the calculation results of the briquette stress state by the Finite element method are presented. The fields of compressive and tensile stresses in briquette are determined. The conditions affecting the process of the briquette destruction are considered.</p>

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Analysis the Cable Replacement Method of Tianjin Yonghe Bridge

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.1383 ◽

2011 ◽

Vol 71-78 ◽

pp. 1383-1387 ◽

Cited By ~ 2

Author(s):

Wen Juan Yao ◽

Wu Yang ◽

Xiao Yu Liu

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Stress State ◽

Main Beam ◽

The Finite Element Method ◽

Replacement Method ◽

Replacement Process ◽

Before And After ◽

Element Method

Taking Tianjin Yonghe bridge for example, the finite element method is adopted to simulate each stages of cable replacement process, the dates of tension, the alignment of main beam and the change of stress before and after cable replacement are compared and analysed, The measured value is greatly consistent with calculated value, Stress state of the bridge has been greatly improved, the weight of main beam bearing by the cable will be shared by a few closed cable after unloading, so the cables which are more serious corroded should be replaced.

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The issues of designing of construction features of the internal combustion cam engine

Combustion Engines ◽

10.19206/ce-2017-444 ◽

2017 ◽

Vol 171 (4) ◽

pp. 259-264

Author(s):

Tomasz BOROWCZYK ◽

Mikołaj SPADŁO

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Internal Combustion ◽

Constant Volume ◽

The Finite Element Method ◽

Starting Point ◽

Piston Mechanism ◽

Crank Mechanism ◽

Element Method

On the pages of the article described cam-piston mechanism developed as an alternative to piston crank mechanism. The main feature of this mechanism is that the piston is dwell in the TDC by the 30°CA and thus allows combustion of the fuel in constant volume. Authors presented the process of designing an analytical cam. The starting point for the calculation was the displacement of piston graph and the limits of acceleration and velocity values obtained. The results of strength calculations of the cam with regard to fatigue problems are also presented. Calculations were carried out in order to reduce the weight of the cam. For this purpose, the Finite Element Method was used.

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Stress analysis for a lug under various conditions

The Journal of Strain Analysis for Engineering Design ◽

10.1243/03093247v291007 ◽

1994 ◽

Vol 29 (1) ◽

pp. 7-16 ◽

Cited By ~ 16

Author(s):

G S Wang

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Stress State ◽

Stress Analysis ◽

Cold Working ◽

Contact Condition ◽

The Finite Element Method ◽

Element Method ◽

Stress Analyses

Stress analyses are performed using the finite element method (FE) for a lug under various conditions. The effects of the clearance between pin and hole, the pin load magnitude, the contact condition, and the relative pin/lug rigidities etc. are investigated. The effect of some durability improvement techniques, such as interference fitting, bushing, and cold working are also investigated. Significant results are obtained which can improve both the understanding of the stress state in a lug and the design of a durable lug.

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Stress state analysis of an equal slope shell under uniformly distributed tangential load by different methods

Structural Mechanics of Engineering Constructions and Buildings ◽

10.22363/1815-5235-2021-17-1-51-62 ◽

2021 ◽

Vol 17 (1) ◽

pp. 51-62

Author(s):

Olga O. Aleshina ◽

Vyacheslav N. Ivanov ◽

David Cajamarca-Zuniga

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Numerical Calculation ◽

Stress State ◽

Difference Method ◽

The Finite Element Method ◽

Calculation Methods ◽

Variational Difference Method ◽

Thin Walled ◽

Element Method

Nowadays there are various calculation methods for solving a wide range of problems in construction, hydrodynamics, thermal conductivity, aerospace research and many other areas of industry. Analytical methods that make up one class for solving problems, and numerical calculation methods that make up another class, including those implemented in computing complexes, are used for the design and construction of various thin-walled structures such as shells. Due to the fact that thin-walled spatial structures in the form of various shells are widely used in many areas of human activity it is useful to understand and know the capabilities of different calculation methods. Research works on the study of the stress-strain state of the torse shell of equal slope with an ellipse at the base are not widely available at the moment. For the first time the derivation of the differential equations of equilibrium of momentless theory of shells to determine the normal force Nu from the action of uniformly distributed load tangentially directed along rectilinear generatrixes to the middle surface of the torse of equal slope with a directrix ellipse is presented in this article. The parameters of the stress state of the studied torse are also obtained by the finite element method and the variational-difference method. The SCAD software based on the finite element method and the program SHELLVRM written on the basis of the variational-difference method are used. The numerical results of the parameters of the stress state of the studied torse are analyzed, and the advantages and disadvantages of the analytical method and two numerical calculation methods are determined.

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