In the present study, a novel windscreen wiperon-cylinder machine has been used to investigate the influence of sliding speed and normal force on the coefficient of friction. Using this machine it is possible to measure the friction force not only on specimen level, as in former studies to be available in the literature, but also on structural level by considering the whole windscreen wiper. As measurement results are strongly influenced by both the real, non-circular cross-section, and the eccentricity of the rotating glass cylinder an analytical model has been developed to explain the measurement results. The good agreement to be found between theory and experiment confirms the validity of the model. Majority of the results belongs to partial contact where the wiper blade is not in contact with the glass countersurface along its total length. After the discussion of experimental results, as a last step, authors made an attempt to compare quantitatively the predictive capability of two different contact models widely used in mixed friction model of sliding rubber components. The results show that the difference in film thickness due to solid-solid contact can be larger than three orders of magnitude in case of a typical windscreen wiper.
The rolling bearings are frequently applied elements of the mechanical structures. During finite element modeling of rolling bearing supported structures to define the adequate accuracy of bearing rigidity behavior enlarge immensely the FE model size and the related calculation time. So it is an understandable effort to use simplified substituting model for rolling bearing which carries the bearing rigidity character and does not make an unnecessary complicated structural model. In this paper the authors present a substituting technique for needle roller bearing.
The present paper shows the standard uniaxial tensile testing, material law identification and finite element simulation of a rubber-cord composite membrane structure used in railway brake systems. The membrane transforms air pressure growth to unidirectional movement within a wide temperature range. A complete procedure will be detailed for the mechanical characterization of the highly complicated sandwich compound built on simple tensile tests. The authors analyze mechanical procedures during deformation using MSC. Marc commercial finite element software. The paper points out the importance of temperature and orientation on an orthotropic structure and highlights the necessity of a reliable material law especially for rubber-cord composites.
The present paper surveys briefly the parameter identification methods widely used in
case of generalized Maxwell-model. Beside those basing on dynamical-mechanical thermal analysis
(DMTA) and stress relaxation measurement authors have presented a technique using simple tensile
tests. The latter can be effectively used by combining it with the genetic algorithm of Matlab for
parameter identification in a limited frequency/time domain. The proposed method can be
generalized easily for example for shear and compression tests too. After comparing it with other
existing methods author make a proposal for the strain rate of the uniaxial tensile test.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.