Patryk Różyło

Experimental and Numerical Study of the Buckling of Composite Profiles with Open Cross Section under Axial Compression

The object of the research are short, thin-walled columns with an open top-hat cross section made of multilayer laminate. The walls of the investigated profiles are made of plate elements. The entire columns are subjected to uniform compression. A detailed analysis allowed us to determine critical forces and post-critical equilibrium paths. It is assumed that the columns are articulately supported on the edges forming their ends. The numerical investigation is performed by the finite element method. The study involves solving the problem of eigenvalue and the non-linear problem of stability of the structure. The numerical analysis is performed by the commercial simulation software ABAQUS®. The numerical results are then validated experimentally. In the discussed cases, it is assumed that the material operates within a linearly-elastic range, and the non-linearity of the FEM model is due to large displacements.

EXPERIMENTAL AND NUMERICAL ANALYSIS OF THE COMPRESSION OF A THIN-WALLED COMPOSITE PLATE

The subject of research is a rectangular plate with a cut-out subjected to regular compression. The plate articulately supported on the short side edges, made of a composite with high strength properties. The study concerned the numerical finite element analysis linear and nonlinear stability of the structure and the experimental validation of the results. The instrument used was a numerical program ABAQUS®.

NUMERICAL ANALYSIS OF THE BEHAVIOR OF COMPRESSED THIN-WALLED ELEMENTS WITH HOLES

The study investigates thin-walled steel elements in a form of openwork beams with holes described by variable geometrical parameters. The specimens are modeled numerically and additionally subjected to axial compression in order to examine the critical and post-critical behavior of the thin-walled profiles. The models of profiles are propped articulatedly on the edges of the cross-section in the upper and lower parts. The numerical analysis investigates only the problem of non-linear stability of these structures. The FEM analysis is stopped at the moment when the compressed profiles achieve the yield stress in order to determine their loss of stability without undesired strains. The numerical computations are performed using the ABAQUS® program to investigate the impact of diameter variability in the thin-walled profiles with holes under allowable operational loads. The numerical investigation was performed only with respect to elastic work, ensuring the stability of thin-walled structures.

NUMERICAL ANALYSIS OF THE CRITICAL STATE OF THIN-WALLED STRUCTURE WITH Z-PROFILE CROSS SECTION

The object of the study was a thin-walled profile with Z-shaped cross section made of the carbon-epoxy composite. The material model was prepared based on the implemented orthotropic properties. The purpose of the study was to determine the value of the critical load at which buckling occurs, the form of buckling and operating characteristics in critical condition. In order to achieve this numerical analysis were carried out. Additionally, the effects of the modification in arrangement of layers of the laminate to the stability and strength of thin-walled composite structures was presented. Numerical studies were carried out using commercial simulation software ABAQUS®. Within the FEM research, both forms of buckling and the associated critical load, dependent on the configuration the layers of the composite were achieved. The analysis of the obtained results allowed the evaluation of the structure’s work in relation to the level of energy consumption or rigidity estimation. In the paper only numerical simulations of the critical state were conducted.

THEORETICAL AND EXPERIMENTAL ANALYSIS OF LOADING IMPACT FROM THE PROGRESSIVE GEAR ON THE LIFT BRAKING DISTANCE WITH THE USE OF THE FREE FALL METHOD

The gear which is the central safety element of the friction drive lift during braking is exposed to overloading connected with changeable weight which loads the lift braking system. In the article the results of numerical analysis for braking process of CHP 2000 type progressive gear distinguished by an innovative design have been presented. The numerical analysis was conducted with the use of a simulation of the gear roller displacement depending on changeable loading with the support of Abaqus/ CAE software. Displacement of the gear roller from the neutral position in which the gear starts loosing energy of speeding up weight to zero was simulated. The results obtained from computer simulations were verified on the basis of a physical experiment at the bench station created to verify braking parameters of the gears with the use of free fall method.

Buckling and limit states of composite profiles with top-hat channel section subjected to axial compression

The subject of the research was a short thin-walled top-hat cross-section composite profile. The tested structure was subjected to axial compression. As part of the critical state research, critical load and the corresponding buckling mode was determined. Later in the study laminate damage areas were determined throughout numerical analysis. It was assumed that the profile is simply supported on the cross sections ends. Experimental tests were carried out on a universal testing machine Zwick Z100 and the results were compared with the results of numerical calculations. The eigenvalue problem and a non-linear problem of stability of thin-walled structures were carried out by the use of commercial software ABAQUS®. In the presented cases, it was assumed that the material is linear-elastic and non-linearity of the model results from the large displacements. Solution to the geometrically nonlinear problem was conducted by the use of the incremental-iterative Newton-Raphson method.The subject of the research was a short thin-walled top-hat cross-section composite profile. The tested structure was subjected to axial compression. As part of the critical state research, critical load and the corresponding buckling mode was determined. Later in the study laminate damage areas were determined throughout numerical analysis. It was assumed that the profile is simply supported on the cross sections ends. Experimental tests were carried out on a universal testing machine Zwick Z100 and the results were compared with the results of numerical calculations. The eigenvalue problem and a non-linear problem of stability of thin-walled structures were carried out by the use of commercial software ABAQUS®. In the presented cases, it was assumed that the material is linear-elastic and non-linearity of the model results from the large displacements. Solution to the geometrically nonlinear problem was conducted by the use of the incremental-iterative Newton-Raphson method.

NUMERICAL ANALYSIS OF THE POSTBUCKLING OF THIN-WALLED COMPOSITE STRUCTURE WITH Z-PROFILE CROSS SECTION

The object of the study was a thin-walled sample made of carbon composite. The studied profile was a z-shaped cross section. The aim of the study was a post critical state analysis by the use of four independent destruction initiation criteria. The numerical analysis was conducted in ABAQUS®. The study presents the critical areas of the composite sample and determines the load values at which initiation criteria were met. The post critical state examination was confronted with previously obtained results of the critical state. In addition, the effect of the laminate layer configuration on the stability and load capacity of the structure is shown.

Comparative analysis of the experimental and numerical research of the stamping process of axially-symmetrical elements

Abstract The paper is concerned with determining the influence of laser treatment process on the properties of electro spark coatings. The properties were assessed after a laser treatment by analysing microstructure and X-ray diffraction and measuring surface geometric structure and microhardness. The studies were conducted using WC-Cu electrodes produced by powder metallurgy of nanostructural powders. The coatings were deposited by means of the EIL-8A model and they were laser-treated with the Nd:YAG, BLS 720 model.Comparative analysis of the experimental and numerical research of the stamping process of axially-symmetrical elements

FEM and Experimental Based Analysis of the Stamping Process of Aluminum Alloy

The subject of the study was aluminum samples of varying thickness. The aim of the study was to perform the experimental stamping process of the samples on a universal testing machine and a numerical analysis on two independent computer systems Abaqus® and Deform-3D. As part of the numerical analysis, bilinear material model was included, taking into account elastic and plastic characteristics. The study was conducted in a dynamic environment with geometric nonlinearity. The results obtained from experimental research were confronted with those obtained by FEM computer simulation. During the research, numerical model of the stamping process has been developed, which was validated with the results of experimental research.

NUMERICAL THERMAL ANALYSIS OF A CAR BRAKING SYSTEM

The study involved performing a numerical thermal analysis of selected components in a car braking system. The primary goal of the study was to determine the regions which are most susceptible to variations in temperature, and to determine the degree of thermal impact upon them. The analysis was performed using the Abaqus environment. The examined components of the braking system were made of materials reflecting mechanical properties of the real subassemblies. The FEM analysis enabled determination of the distribution of temperature in the system with respect to the properties of the investigated materials and applied boundary conditions.