This issue of Journal has the special part, that is prepared by Dr. Juergen Jaeger, Guest Editor, our Partner in framework of this International Scientific Edition, Specialist in area of Contact Mechanics. Presented papers subject is very important in Engineering domain both from theoretical and from applied view point.

Preface of the Guest Editor

Extended versions of some selected papers, which have been presented at the conference Contact Mechanics in March 2003 in Crete, are presented here. The meeting was organized by the Wessex Institute of Technology (WIT), as the sixth of a series, which started in Southampton (UK) in 1993 and was continued every two years. These conferences provide a forum for the discussion of different aspects of contact mechanics. Major disciplines have been computational methods, analytical models and experimental results in contact mechanics, fracture, fatigue and wear. Future meetings will include surface treatment. The proceedings of this conference can be found in the reference below.

Modern computer technology of the last few years has provided new methods and solutions for contact problems. Contact processes are inherently non-linear due to moving boundaries and the existence of frictional and other non-linear effects along the contact surfaces. The early theory of contact mechanics was developed by Russian scientists at the beginning of the 20^th century, with emphasis on mathematical methods. In engineering analysis, simplified results have been used for along time. Classical examples, which are familiar to most mechanical engineers are Hertzian pressure (Hertz 1882), Carter's theory for rolling (1926) and elastic foundations by Winkler (1867). Modern design of machine elements requires the calculation of local stress distributions, considering cyclic loading, fatigue, and wear. New computer programs can solve such problems with an acceptable output of time and hardware. In the series of WIT-conferences, substantial developments have been published, which help to understand the influence of friction, heating, non-elastic material behaviour, metal forming, rolling, impact, and others, on contact processes. Special sections have also been presented in hand books by WIT.

Delegates from all over the world presented about 30 contributions at the conference. The scope of current research activities at the meeting can be divided roughly in the following groups

ћ          Computational methods

ћ          Residual stress effects

ћ          Damage mechanics

ћ          Experimental and computational methods

ћ          Fatigue and wear

Recently, considerable improvements in computer technology and experimental measurements resulted in solutions for complex practical problems, providing accurate and efficient results. A few contributions are presented in this edition, on vibration damping of foundations, design of highly stressed machine components, residual stresses during grinding, and the mathematical modeling of elasto-visco-plastic contact problems.

Reference

Computational methods in contact mechanics VI, editor: C.A.Brebbia, Wessex Institute of Technology, WIT-Press, Southampton, UK, ISBN: 1-85312-963-1,љљљљљљљљљ http://www.wessex.ac.uk

 

The papers presented here (special section)

F. Kirzhner, G. Rosenhouse, Y. Zimmels (Israel). Attenuation of vibration in rock by elastic replacement.

V. Kujanpää, H. Martikka (Finland). Analytical and nonlinear FEM simulation of contact damage of hardened gears.

R. Błaszków, L. Kukiełka, R. Patyk, M. Wojtalik (Poland). Numerical analysis of nonlinear contact problem in processes of rolling and grinding.

L. Kukiełka (Poland). Nonlinear modelling for elasto/visco-plastic contact problem in technological processes.

 

 

 

Juergen Jaeger Ph.D.; Mechanical design engineer at Lauterbach Verfahrens-technik in Karlsruhe, Germay. Published 40 papers and a forthcomming book on "New solutions in Contact Mechanics", WIT-press, 2004, ISBN: 1-85312-994-1. Scientific interest: Contact mechanics, impact, friction, fatigue and wear. www.JuergenJaeger.de