Sökning: "frictional contact"

Visar resultat 11 - 15 av 88 avhandlingar innehållade orden frictional contact.

  1. 11. Optimization of Structures in Contact

    Författare :Daniel Hilding; Georgios E. Stavroulakis; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This dissertation addresses the problem of developing theory, algorithms and computational methodology for optimization of structures in contact. Three particular research problems are studied: (i) developing efficient and reliable optimization algorithms for solving structural optimization problems including contact, (ii) creating more realistic state problems for structures in frictional contact, and (iii) developing computational methodology for shape optimization of structures in frictionless contact. LÄS MER

  3. 12. Analysis of Ball CV-joints of Fixed Type

    Författare :Peter Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frictional forces; displacements; contact angles; load distribution;

    Sammanfattning : Two theoretical models for analysing ball CV-joints of fixed type are presented. The models, which have been implemented in computer programs, calculate internal conditions such as load distribution, contact angles and displacements for different operating conditions. LÄS MER

  4. 13. Squat defects and rolling contact fatigue clusters - Numerical investigations of rail and wheel deterioration mechanisms

    Författare :Robin Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rail surface irregularities; rolling contact fatigue clusters; dynamic vehicle–track interaction; rolling contact fatigue; studs; squats; fracture mechanics;

    Sammanfattning : Squat defects, a type of localised rolling contact fatigue damage appearing on rail surfaces with rail break as an ultimate consequence, have concerned infrastructure managers for the last couple of decades. In recent years similar types of defects—so-called studs—that are visually resembling squats, have started to appear. LÄS MER

  5. 14. Ghosts and machines : regularized variational methods for interactive simulations of multibodies with dry frictional contacts

    Författare :Claude Lacoursière; Bo Kåggström; Ander Klarbring; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Discrete mechanics; Variational method; Contact problems; Impacts; Least action principle; Saddle point problems; Lagrange Multipliers; Constrained systems; Multibody Systems; Numerical regularization; Constraint realization; Constraint stabilization; Dry friction; Differential Algebraic Equations; Nonsmooth problems; Linear Complementarity; Quaternion algebra; Numerical linear algebra; Physics modeling; Interactive simulation; Numerical stability; Rigid body dynamics; Dissipative systems; Computational physics; Beräkningsfysik;

    Sammanfattning : A time-discrete formulation of the variational principle of mechanics is used to provide a consistent theoretical framework for the construction and analysis of low order integration methods. These are applied to mechanical systems subject to mixed constraints and dry frictional contacts and impacts---machines. LÄS MER

  7. 15. Crack growth paths in rolling contact fatigue — Numerical predictions

    Författare :Mohammad Salahi Nezhad; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vector crack tip displacement; Crack face friction; Crack growth direction; Crack propagation; Rolling contact fatigue;

    Sammanfattning : Rolling contact fatigue (RCF) cracks in railway wheels and rails are costly and complex to deal with. Despite the extensive research efforts that have been put into understanding the mechanisms and developing appropriate predictive models for RCF crack growth, there are still a lot of open questions. LÄS MER