Sökning: "frictional instability"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden frictional instability.

  1. 1. Time-domain modelling of high-frequency wheel/rail interaction

    Författare :Astrid Pieringer; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; wheel rail interaction; railway noise; roughness; time domain; frictional instability; discrete irregularities; transient contact; non-Hertzian contact;

    Sammanfattning : The interaction between wheel and rail is the predominant source of noise emission from railway operations in a wide range of conventional speeds. On the one hand, this wheel/rail noise concerns rolling noise and impact noise caused by the vertical interaction excited by roughness and discrete irregularities of the wheel/rail running surfaces, respectively. LÄS MER

  2. 2. Engineering model for curve squeal formulated in the time domain

    Författare :Ivan Zenzerovic; Chalmers University of Technology; []
    Nyckelord :tangential point-contact model; time domain; frictional instability; Curve squeal; rolling contact; non- Hertzian contact;

    Sammanfattning : Curve squeal is a type of railway noise that may arise when a railway vehicle negotiates a relatively tight curve. Squeal is common in curves of a radius lower than 200 meters. A single frequency dominates the radiated sound, which makes squeal a very tonal noise. LÄS MER

  3. 3. Time-domain modelling of curve squeal: a fast model for one- and two-point wheel/rail contact

    Författare :Ivan Zenzerovic; Chalmers University of Technology; []
    Nyckelord :two-point contact; non-Hertzian contact; dynamics coupling; rolling contact; tangential point-contact model; Curve squeal; time domain; frictional instability;

    Sammanfattning : Curve squeal is a type of railway noise that may arise when a railway vehicle negotiates a relatively tight curve. A single frequency, corresponding to a wheel mode, dominates the radiated sound, which makes squeal a very tonal noise. LÄS MER

  4. 4. Numerical simulation of thermomechanically coupled transient rolling contact - An arbitrary Lagrangian-Eulerian approach

    Författare :Andreas Draganis; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thermomechanical coupling; finite element method; transient analysis; arbitrary Lagrangian--Eulerian; rolling contact; frictional contact;

    Sammanfattning : Numerical simulation of rolling contact serves as an important complement to laboratory and full-scale testing in the endeavour to further the understanding of related physical mechanisms, e.g. the influence of friction on the rolling motion, the thermomechanical interaction, damage phenomena and related modes of failure. LÄS MER

  5. 5. Of Pipes and Bends

    Författare :Jacopo Canton; Philipp Schlatter; Ramis Örlü; Dwight Barkley; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear instability; bifurcation; flow control; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : This work is concerned with the transition to turbulence of the flow in bent pipes, but it also includes an analysis of large-scale turbulent structures and their use for flow control.The flow in a toroidal pipe is selected as it represents the common asymptotic limit between spatially developing and helical pipes. LÄS MER