finite element method

NUMERICAL MODELING AND DETERMINATION OF THE STRESS-STRAIN STATE OF RAILWAY WHEELS WITH THE PRESENCE OF SUBSURFACE PHYSICAL TYPE STRESS CONCENTRATORS

Problem statement. The problem of establishing the stress-strain state of carriage wheels with the presence of subsurface inclusions is considered. Purpose. The purpose of this article is to build a methodology to establish dependence between the parameters of subsurface inclusions and the contact strength of railway wheels. Methodology. Based on modern models of the mechanics of a deforming solid of non-local (gradient) media, approaches to assessing the strength of structures and methods of mathematical modeling, the spatial distribution of the field of displace

Oblique stagnation-point flow of ternary hybrid nanofluid towards a shrinking surface

The oblique stagnation-point flow of a ternary hybrid nanofluid towards a shrinking surface is studied numerically in this paper.  A similarity transformation was used to convert the governing equations into a set of ordinary differential equations, which were then solved numerically using the bvp4c solver in MATLAB software.  The research, involving three different nanoparticles, provides valuable insights into their impact on the fluid dynamics and heat transfer characteristics of the system under study.  The influence of the parameters $S$, $\lambda$ and nanoparticle

HIGH-PERFORMANCE COMPUTING METHOD FOR INVESTIGATING HEAT CONDUCTION PROCESSES IN COMPOSITE MATERIALS

This study explores an approach to modeling heat conduction in composite materials using high-performance computing methods. The solution of a complex mathematical problem is decomposed into multiple independent processes through the MPI method to maximize computational efficiency. The model structure accounts for the properties of the composite material and its components. The finite element method (FEM) is applied to study the thermal properties.

Effect of nanoparticle shape on natural convection in hybrid nanofluid inside square cavity

A numerical study of natural convection in a square cavity with Al$_2$O$_3$-Cu/water hybrid nanofluid, focusing on the effects of nanoparticle shape, is conducted.  The governing partial differential equations and corresponding boundary conditions are transformed into nondimensional forms and solved using the finite element method.  The flow and heat transfer characteristics are graphically illustrated and explained for different nanoparticle volume fractions and shapes, with corresponding average Nusselt numbers.  It has been observed that a variety of nanoparticle sha

NONLINEAR MODELING AND ANALYSIS OF DAMAGED REINFORCED CONCRETE BEAMS USING ANSYS AND LIRA-SAPR SOFTWARE PACKAGES

This article presents a comparative analysis of the nonlinear behavior of a reinforced concrete beam with damaged reinforcement in the tension zone under a gradually increasing load until failure. The experimental beam, measuring 2100 mm × 200 mm × 100 mm, consists of a 20 mm diameter rebar in the tension zone, two 6 mm diameter rebars in the compression zone, and 6 mm diameter stirrups spaced 75 mm apart for transverse reinforcement. Nonlinear calculations were performed using ANSYS and LIRA-SAPR, with identical initial conditions applied to both models for accurate comparison.

Numerical studies of a Timoshenko system with the second sound

Timoshenko's problem is not a recent problem and many articles exist concerning his study.  New physical problems appear and require a good mathematical understanding of the behavior of this phenomenon.  Our contribution will consist in studying the numerical stability of a Timoshenko system with second sound.  We introduce a finite element approximation and prove that the associated discrete energy decreases and we establish a priori error estimates.  Finally, some numerical simulations are obtained.

STUDY OF THE CUTTING FORCE BASED ON THE OBTAINED UNDEFORMED CHIPS DURING CUT IN WHEN MACHINING AN INTERNAL GEAR BY POWER SKIVING METHOD

This article explores the formation of non-deformed chips during the cut-in of an internal toothed ring using the Power Skiving method. This pivotal stage of the cutting process poses significant hazards not only in gear cutting but also in any cutting operation. The study involved modeling the process at the initial stage for various technological parameters, including cut-in depth and number of working passes. To achieve non-deformed chips, a methodology developed for worm milling was applied.

Numerical approximation of the MGT system with Fourier's law

In this paper, we consider the Moore–Gibson–Thompson–Fourier system made by coupling the Moore–Gibson–Thompson (MGT) equation with the classical Fourier heat equation known as the MGT–Fourier model.  For $\sigma=\alpha\beta-\gamma>0$, the authors used the semi-group method to prove the existence and uniqueness of global solutions and the exponential stability of total energy.  Our contribution will consist in studying numerical method based on finite element discretization in the spacial variable $x$ and finite difference schema in time of the MGT–Fourier model.  A d

A parallel preconditioning Schur complement approach for large scale industrial problems

The purpose of this paper is to introduce a new strategy to improve the convergence and efficiency of the class of domain decomposition known as Schur complement techniques related to interface variables for the simulation of mechanical, electrical and thermal problems in presence of cross points.  More precisely, we are interested not only in domain decomposition with two equal parts having the same physical properties but rather in more general splitting components.  It is known that in the first case, the optimal convergence with good pre-conditioner is obtained in t

АNALYSIS OF SOFTWARE PACKAGES APPLYING IN THE INVESTIGATION OF THE DAMAGE EFFECT TO REINFORCED CONCRETE BEAMS ON STRENGTH AND DEFORMABILITY: THE REVIEW

Currently, on the world market, there are trends in the construction of a large number of monolithic and prefabricated reinforced concrete structures, and individual parts of these structures are operated with damage or defects, and the causes of these damages are quite diverse. In modern conditions, such work can be facilitated and analyzed in more detail with the help of specialized software, which can include all the necessary characteristics of material behavior and include existing defects or damage.