Andrzej Baier

Computer-aided strength analysis of the modernized freight wagon

In the paper results of computer-aided strength analysis of the modernized freight wagon based on Finite Element Method are presented. CAD model of the considered freight wagon was created and its strength was analysed in agreement with norms described the way of such kind of freight wagons testing. Then, the model of the analysed freight wagon was modernized by adding composite panels covering the inner surface of the vehicle body. Strength analysis was carried out once again and obtained results were juxtaposed. This work was carried out in order to verify the influence of composite panels on the strength of the freight car body and to estimate the possibility of reducing the steel shell thickness of the box in order to reduce weight of the freight wagon.

Carbon fiber based composites stress analysis. Experimental and computer comparative studies

Composite materials used nowadays for the production of composites are the result of advanced research. This allows assuming that they are among the most elaborate tech products of our century. That fact is evidenced by the widespread use of them in the most demanding industries like aerospace and space industry. But the heterogeneous materials and their advantages have been known to mankind in ancient times and they have been used by nature for millions of years. Among the fibers used in the industry most commonly used are nylon, polyester, polypropylene, boron, metal, glass, carbon and aramid. Thanks to their physical properties last three fiber types deserve special attention. High strength to weight ratio allow the use of many industrial solutions. Composites based on carbon and glass fibers are widely used in the automotive. Aramid fibers ideal for the fashion industry where the fabric made from the fibers used to produce the protective clothing. In the paper presented issues of stress analysis of composite materials have been presented. The components of composite materials and principles of composition have been discussed. Particular attention was paid to the epoxy resins and the fabrics made from carbon fibers. The article also includes basic information about strain measurements performed on with a resistance strain gauge method. For the purpose of the laboratory tests a series of carbon - epoxy composite samples were made. For this purpose plain carbon textile was used with a weight of 200 g/mm2 and epoxy resin LG730. During laboratory strain tests described in the paper Tenmexs delta type strain gauge rosettes were used. They were arranged in specific locations on the surface of the samples. Data acquisition preceded using HBM measurement equipment, which included measuring amplifier and measuring head. Data acquisition was performed using the Easy Catman. In order to verify the results of laboratory tests numerical studies were carried out in a computing environment, Siemens PLM NX 9.0.For this purpose, samples were modeled composite corresponding to real samples. Tests were made for boundary conditions compatible with the laboratory tests boundary conditions.

Examination of a Cargo Space of a Freight Wagon Modified with Composite Panels

This article presents the method of solving the problem considered with the too fast wearing of a steel sheet paneling of a freight wagon body. The method, described in the work, bases on the use of additional components, which are made of composite materials. The proposed solution is based on the appropriate lining of the inside of a wagon body with composite panels. In order to verify the placing and fixing of composite panels to wagon walls, as well as to verify the behavior of joined composite panels in the given conditions of a wagon work it was used a computer analysis basing on the finite element method. Because of the scale of the analyzed problem it was also created a virtual model of the research stand, which allows experimentally verifying phenomena occurring between the joined composite panels mounted on walls of a freight wagon that is made in a natural size. Carried out researches allowed determining the method of arrangement the composite panels in the inside space of a freight wagon body. It was also determined the method of panels joining and the method of their fixing to the steel paneling of a wagon body. It was also determined the procedure of transferring the results of the experimental analysis of the wagon walls, made in a natural size, on a real object using the matching of a virtual model.

Virtual Simulation of Mechatronics Laboratory

Technology of virtual reality made large progress in the last few years. With desktop VR systems it’s possible to present artificial worlds using ordinary PC computer. Creating virtual equivalent of really existing laboratory was major aim of work described in this paper. Also there were created virtual laboratory classes. Application EON Studio from EON Reality was mainly used to achieve this. In this paper a process of building the simulation is presented, used programs are mentioned and final effects are shown.

Molding of strength testing samples using modern PDCPD material for purpose of automotive industry

The casting of metal materials is widely known but the molding of composite polymer materials is not well-known method still. The initial choice of method for producing composite bodies was the method of casting of PDCPD material. For purpose of performing casting of polymer composite material, a special mold was made. Firstly, the 3D printed, using PLA material, mold was used. After several attempts of casting PDCPD many problems were encountered. The second step was to use mold milled from a firm and dense isocyanate foam. After several attempts research shown that this solution is more resistant to high-temperature peak, but this material is too fragile to use it several times. This solution also prevents mold from using external heating, which can be necessary for performing correct molding process. The last process was to use the aluminum mold, which is dedicated to PDCPD polymer composite, because of low adhesiveness. This solution leads to perform correct PDCPD polymer composite material injection. After performing casting operation every PDCPD testing samples were tested. These results were compared together. The result of performed work was to archive correct properties of injection of composite material. Research and results were described in detail in this paper.

Application of Programs of the CAD/CAE Class for Creating the Virtual Laboratory Stand

The article presents the stages of creating a virtual laboratory stand for performing the cycle of tests of the system response to dynamic excitation. To create the virtual laboratory stand was used the PLM Siemens NX 8.5 software. It was shown the method of realization the dynamic analysis in the Motion Simulation module, which result was the characteristic (form) of the system excitation. Then, on the virtual laboratory stand, was conducted the analysis of vibration of the investigated system realized in the Advanced Simulation module. For calculations was used the “Response Simulation” solver, which allows analyzing the system responses to dynamic excitations. Next the results were compared with vibrations measurements made on the real laboratory stand. This lets to verify and adjust the created FEM model.

Investigations of Composite Panels Mounted in the Cargo Space of a Freight Wagon

The paper presents a series of experimental and numerical studies, carried out under the project number PBS2/A6/17/2013 realized as a part of the Applied Research Program, funded by the National Research and Development Centre. The aim of this project is to develop technology, manufacture, and assembly of composite panels on the side of a freight wagon in order to prolong the this operation. The article describes research which aimed to strength analysis of the side of the freight wagon and analysis of the behavior of structural connections of composite panels mounted on the side of the wagon. These studies were carried out on the test bench developed by the authors. During the research stresses and displacements has been analyzed at selected structural elements of the wagon before and after the modifications. The research also included an analysis of the behavior of the connections composite panels with steel components by static extortion on the side of the wagon. In parallel with the ongoing laboratory research steps have been taken to set up a FEM model by means of which was carried out similar numerical studies. Comparison of the results made it possible to adjust (tune) FEM model.

Computer Modeling and Research of FML Composites Using the Method of Features

The use of modern materials, such as composite materials, enabling the production of new or modifying the existing design solutions, and improvement of their technical characteristics in their use in the design, engineering and manufacturing process, allows achieving an improvement of their endurance, physical and chemical properties to match the features and functionality that comply with assumptions. In research studies, it has been proposed to systematize and formalize features in the context of modeling and fabrication of objects created on the basis of structural fiber composites. The result of the study and analysis will be precisely adapted algorithm of the design and construction process and also fabrication of the structural objects made upon using composite materials. The process of multicriteria optimization and stress analysis upon using CAx-class software will enable to reduce the probability of failure or damage to the modified component.

Numerical Modeling of the Phenomena of Frictional Coupling between Wheel and Rail to Describe and Verify the Operation of Surface Condition Detector

Presentation of the numerical model describing a design and functionality of the prototype of surface condition detector is the paper subject. The detector, by monitoring the frictional coupling between so-called “tracking wheel” of the dedicated measuring transducer and a rail can analyse the condition of rail surface (presence of any factor that can deteriorate friction coefficient) [1]. Signal generated at the detector outlet, carrying information about local condition of rail surface, can be used to adjust braking torque of vehicles or machines moving on a track. Authors expect that implementation of the method will eliminated dangerous elongation of braking distance of rail vehicles in the result of loss of adhesion. Structure of detector of rail surface condition is described and its principle of operation is presented in a form of numerical model. Results of numerical simulations are given and they are compared with the measurements taken on the testing facility in real conditions.

Strain Analysis of an Epoxy Resin Based Composites – Laboratory and Simulation Comparative Studies

In this paper issues of stress analysis of composite materials are presented. The components of composite materials and principles of composition has been discussed. Particular attention was paid to the epoxy resins and the fabrics made from carbon fibers. The article also includes basic information about strain measurements performed on with a resistance strain gauge method. For the purpose of the laboratory tests a series of carbon - epoxy composite samples were made. The main aim of the studies was to compare the results of two different research methods – laboratory and simulation method. During laboratory strain tests described in the paper, a composite samples were loaded with a specified load. Tenmexs delta type strain gauge rosettes were used to measure strain. They were arranged in specific locations on the surface of the samples. Data acquisition procedure were carried out using HBM measurement station. Numerical studies were carried out in a computing environment, Siemens NX 9.0. The results of simulation and laboratory tests were compared and presented in the form of graphs. They allow you to validate the method of laboratory measurements. The results of both research types have shown the percentage difference between them for individual loads applied to each composite.