scholarly journals Wear Processes in a Mechanical Friction Clutch: Theoretical, Numerical, and Experimental Studies

2015 ◽  
Vol 2015 ◽  
pp. 1-28 ◽  
Author(s):  
Dariusz Grzelczyk ◽  
Jan Awrejcewicz

Mathematical modeling, theoretical/numerical analysis, and experimental verification of wear processes occurring on the contact surface of friction linings of a mechanical friction clutch are studied. In contrast to many earlier papers we take into consideration wear properties and flexibility of friction materials being in friction contact. During mathematical modeling and numerical simulations we consider a general nonlinear differential model of wear (differential wear model) and a model of wear in the integral form (integral wear model). Equations governing contact pressure and wear distributions of individual friction linings, decrease of distance between clutch shields, and friction torque transmitted by the clutch are derived and compared with experimental data. Both analytical and numerical analyses are carried out with the qualitative and quantitative theories of differential and integral equations, including the Laplace transform approach to ODEs. We show that theoretical results and numerical simulations agree with the experimental data. Finally, a numerical analysis of the proposed mathematical models was carried out in a wider range of parameters of the considered system.

2011 ◽  
Vol 21 (10) ◽  
pp. 2861-2869 ◽  
Author(s):  
J. AWREJCEWICZ ◽  
D. GRZELCZYK

This work is devoted to modeling and the analytical/numerical analysis of tribological processes occurring on the contact surface of shields of a mechanical friction clutch. Although the considered problems have been already studied earlier, however, simplified mathematical models have been used and applied. Unlike previous works, our work takes into account elasticity and wear properties of material of shields rubbing themselves. A general nonlinear differential model of wear is considered, as well as a wear model in the integral form taking into account gradual decrease of speed of wear of shields as a result of abrasive adapting to each other in the process of the exploitation. Equations modeling contact pressure on the contact surface of shields are derived and they yield the contact pressure and the wear of the shields. An analytical/numerical analysis is carried out with the qualitative and quantitative theories of differential and integral equations, including Laplace transformation. Many interesting results are obtained, illustrated and discussed. The presented results can be widened and used in other disciplines of the science, for instance, in physics of solids or biomechanics of various human joints.


2016 ◽  
Vol 66 (1) ◽  
pp. 17-26 ◽  
Author(s):  
Michal Šofer ◽  
Rostislav Fajkoš ◽  
Radim Halama

AbstractThe main aim of the presented paper is to show how heat treatment, in our case the induction hardening, will affect the wear rates as well as the ratcheting evolution process beneath the contact surface in the field of line rolling contact. Used wear model is based on shear band cracking mechanism [1] and non-linear kinematic and isotropic hardening rule of Chaboche and Lemaitre. The entire numerical simulations have been realized in the C# programming language. Results from numerical simulations are subsequently compared with experimental data.


2014 ◽  
Vol 617 ◽  
pp. 215-220 ◽  
Author(s):  
Andrey Benin ◽  
Galina Bogdanova ◽  
Sergey Semenov

The experimental studies of flat and relief glass-plastic reinforcement bond with concrete were conducted. The comparative analysis of obtained experimental data with results of other researchers in field of reinforcement and concrete bond was made. It was identified that composite reinforcement with flat winding has better bond characteristics in comparison with steel reinforcement and other winding types composite reinforcement. The analytical dependencies, allowing to simulate the process of fiber-plastic reinforcement bond with concrete, were obtained. The finite element modeling of deformation process of concrete foundation of transport constructions with fiber-plastic reinforcement were made.


2020 ◽  
pp. 44-49
Author(s):  
V. V. Kharlamov ◽  
◽  
D. I. Popov ◽  
P. S. Sokolov ◽  
L. E. Serkova ◽  
...  

The article presents the results of comparison of experimental studies and mathematical modeling of the stand for testing induction motors by the method of mutual load. A detailed description of the composition of the experimental equipment, which is based on a pair of frequency converters and connected to them a pair of engines of the АИС71В4 type with a nominal power of 0,75 kW, the shafts of which are rigidly connected by a coupling. The mathematical model of the electromechanical system used in the calculations is presented, and its main assumptions are listed. A table of parameter values and graphs obtained from calculated and experimental data are presented. The analysis of the obtained data shows the possibility of using the considered mathematical model with the existing assumptions in the design of electrical complexes intended for testing induction motors by the method of mutual load


2004 ◽  
Vol 41 (5) ◽  
pp. 814-830 ◽  
Author(s):  
Denny Tami ◽  
Harianto Rahardjo ◽  
Eng-Choon Leong ◽  
Delwyn G Fredlund

A physical model was designed and constructed to study the mechanisms associated with capillary barriers for slope stabilization purposes. Prior to construction of the model, various numerical analyses were conducted to determine the optimum dimensions and appropriate soil types for the materials of the capillary barrier model. This paper is divided into three sections: the first two sections are related to the design of the model and are to obtain the optimum dimensions of the model and to investigate the range of soil properties that are most suitable for experimental studies in the laboratory; and the last section is laboratory verification of the numerical analysis where the numerical simulation results are compared with the experimental data. Based on the numerical simulation results, the physical capillary barrier model was constructed using two different combinations of soils, namely silty sand over gravelly sand and fine sand over gravelly sand. From the comparison of the numerical results and experimental data, it was found that the numerical analysis was able to simulate the experiment on the physical capillary barrier model reasonably well.Key words: physical capillary barrier model, unsaturated water flow, numerical simulation, pore-water pressure, volumetric water content, slope stability, infiltration.


2016 ◽  
Vol 136 (9) ◽  
pp. 1261-1267
Author(s):  
Fumiya Kinoshita ◽  
Yuki Mori ◽  
Yasuyuki Matsuura ◽  
Hiroki Takada ◽  
Masaru Miyao

Author(s):  
Larissa Steiger de Freitas ◽  
Marcus Vinícius Canhoto Alves ◽  
Rafael Rodrigues Francisco

2018 ◽  
Vol 84 (10) ◽  
pp. 23-28
Author(s):  
D. A. Golentsov ◽  
A. G. Gulin ◽  
Vladimir A. Likhter ◽  
K. E. Ulybyshev

Destruction of bodies is accompanied by formation of both large and microscopic fragments. Numerous experiments on the rupture of different samples show that those fragments carry a positive electric charge. his phenomenon is of interest from the viewpoint of its potential application to contactless diagnostics of the early stage of destruction of the elements in various technical devices. However, the lack of understanding the nature of this phenomenon restricts the possibility of its practical applications. Experimental studies were carried out using an apparatus that allowed direct measurements of the total charge of the microparticles formed upon sample rupture and determination of their size and quantity. The results of rupture tests of duralumin and electrical steel showed that the size of microparticles is several tens of microns, the particle charge per particle is on the order of 10–14 C, and their amount can be estimated as the ratio of the cross-sectional area of the sample at the point of discontinuity to the square of the microparticle size. A model of charge formation on the microparticles is developed proceeding from the experimental data and current concept of the electron gas in metals. The model makes it possible to determine the charge of the microparticle using data on the particle size and mechanical and electrical properties of the material. Model estimates of the total charge of particles show order-of-magnitude agreement with the experimental data.


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