Wyniki wyszukiwania - Biblioteka Nauki

1

Selected aspects of power distribution for 4wd vehicle driven by diagonal power transmission

100%

Baier A. , Mydlarz J.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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tom Vol. 44, nr 1

73--79

EN

Purpose: Paper describes phenomena related to the vehicle acceleration on the curve, with the high speed, considering inertia forces and driving force. Design/methodology/approach: The phenomena were investigated with three tools: classical analytical mechanics, computer simulation and tests with physical model. Findings: Simulations and physical tests led to similar results. However, new diagonal transmission system showed advantages only on slippery surface of the test track. Nevertheless such a behavior resulted in conclusion that diagonal transmission system would be useful influencing vehicle safety, specifically at slippery roads. Practical implications: There is a possibility of diagonal transmission system application for sport vehicles to improve performance. For utilitarian vehicles increasing safety is the most important aspect, especially in cooperation with ESP system. When it comes to special and military vehicles both mentioned above features are desired. Possible power-pack application is an additional advantage. Originality/value: The goal was the comparison of standard 4x4 transmission system with unconventional patented 4x4 transmission system called diagonal one.

2

Modelling of coal in a railway coach

88%

Baier A. , Majzner M.

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tom Vol. 45, nr 2

163--169

EN

Purpose: Objective of the study was to identify the forces acting on the structural elements of railway wagons. It is part of research conducted under a grant, on the use of composites in the repair and construction of new structural elements of railway wagons. Design/methodology/approach: The main tool of verification of the research is Siemens PLM Software NX 7.5. Motion simulation has been carried out in one module of the software, Motion Simulation. Connections between components have been made using constraints and connections mapping the real relationship between components. Findings: The aim of the study was to identify the forces acting on the door, and establish a database of input for further research. Research limitations/implications: The main limitations of the study were the possibility of mapping all the connections of components, in the same way as in reality. The second limitation was the maximum length of track, depending on the number of possible landmarks in which it was possible the measurement of variables. Originality/value: Results of the analysis of the wagon constructed with the standard steel components are input data to research on the modification of structural components on the basis of fibrous composite The results obtained are an example of application of the methods of computer analysis, on the basic type of testing wagons. Completed study is the first step in a study of movement railway wagon in further stages will be possible to perform the studies in more complex aspects of the movement.

3

Numerical analysis of stress state during single point bending in DMTA examinations

75%

Gnatowski A. , Palutkiewicz P. , Bociąga E.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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tom Vol. 28, nr 1

47-50

EN

Purpose: Determination of stresses at the change of Young's modulus values in temperature function for samples made of PA 6.6 filled with glass fibre, by DMTA method, was the aim of work. Design/methodology/approach: Investigations were carried out for samples subjected to the one-axial bending. The change in the value of the dynamic Young modulus and the mechanical loss tangent in function of temperature and oscillation frequency by the DMTA method was determined. The computer simulations of changes of the stress and strain distribution within the range of elastic strains and the glass transition phase were done. Findings: Examinations made possible the determination of dynamic mechanical proprieties PA 6.6 filled with glass fibre and changes in the stress distribution during the dynamic loading of the sample in function of temperature. Higher values of the Young modulus were observed within the range of elasticity and the glass transition phase. The stress increased with the increase in Young's modulus, at the strain generated from push rot oscillation. Research limitations/implications: The accuracy of used approximate method for computer simulations was not sufficient to indicate the Bielajew point. Practical implications: Investigated polymeric composite is characterized by viscoelastic properties, so all indicators of the physical and chemical properties depend on not only the time but and also the temperature. Originality/value: To characterize properties of investigated composite and to estimate the composite usage in particular conditions, dependences of the storage module and the mechanical losses tangent was determined in function of temperature at the one-axial bending.

4

Application of feature method to the modelling of composite structural elements

63%

Beier A. , Majzner M.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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tom Vol. 45, nr 1

30--38

EN

Purpose: The paper describes the use of object-oriented methods in modelling and analysis of components made of fibre-based composites. Defined and specified the method for creating fibre primitives. An algorithm for the design of composite structures using object-oriented methods. Design/methodology/approach: The basic tool is an algorithm to build fibre facilities. Material properties can be found in the previously created databases of material objects. The whole is linked to the relevant formulas and diagrams. Findings: The basis for the introduction of object-oriented method was to systematize the processes of modelling and analysis of composite materials. Application issue features possible to determine the final form of composite structure. Research limitations/implications: Research direction is to create tools to support the work of the constructor during the construction of composite components. Material created a database of individual components of laminates, allows to build optimal in terms of established criteria of composite elements. Practical implications: The practical aspect of using object-oriented method is to use it to define the structure of the laminates. At the modelling stage it is possible to perform the parameterization formula of each phase of the composite. This recipe is especially important during the manufacture of composites. Originality/value: The paper presents a new approach to modelling of composites by defining a new elementary objects forming the basis for during the composite design process. Algorithms used in the work are particularly important for designers of new technical components made on the basis of fibre composites.

5

Modelling of inelastic behaviour of reinforced concrete deep beam

63%

Cichorski W. , Stolarski A.

Journal of Achievements in Materials and Manufacturing Engineering

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2016

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tom Vol. 74, nr 1

37--44

EN

Purpose: An analysis of the static load - carrying capacity of rectangular reinforced concrete deep beam taking into account the physical nonlinearities of structural materials: concrete and reinforcing steel, was the aim of the paper. Design/methodology/approach: The model of the elastic-perfectly plastic material was applied for the reinforcing steel. The reduced, static form of non-standard model of dynamic deformation, with regard to the material softening was applied for the concrete. The method of structure effort analysis was developed using the finite element method. Findings: The results of numerical solutions were presented with comparison to the experimental results and other numerical results taken from the literature. Very good agreement of the numerical results was obtained in comparison with the experimental results in the range of the load - carrying capacity and the displacement state analysis. Research limitations/implications: The effectiveness of the method analysis and computational algorithms for the problems of numerical simulation of reinforced concrete deep beam behaviour was indicated in the paper. Practical implications: The developed method can be applied to the effort analysis of the different reinforced concrete structural elements behaving in the complex stress states. Originality/value: The stress state in the deep beam was illustrated in the form of the stress distribution over the characteristic cross-sections as well as in the form of the scheme of the material effort on the surface of the structure.