Sökning: "nonlinear contact"

Visar resultat 1 - 5 av 47 avhandlingar innehållade orden nonlinear contact.

  1. 1. Vibrations induced by surface roughness in nonlinear rolling contacts

    Författare :Oskar Erik Lundberg; Ines Lopez Arteaga; Svante Finnveden; Will Graham; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rolling contact; nonlinear contact; contact stiffness; contact filter; state-dependent method; relative displacement; wheel-rail contact; Vehicle and Maritime Engineering; Farkostteknik;

    Sammanfattning : For efficient transportation in either trains, busses or passenger cars, rolling elements such as wheels, tyres, bearings and transmission elements are fundamental. The energy efficiency and the generation of noise and vibrations in rolling contacts depend on the surface roughness of contacting bodies. LÄS MER

  3. 2. Probing nonlinear electrical properties at the nanoscale : Studies in multifrequency AFM

    Författare :Riccardo Borgani; David B. Haviland; Peter Grütter; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURVETENSKAP; NATURAL SCIENCES; Atomic Force Microscopy; Nonlinear dynamics; Multifrequency; Contact potential difference; Conductance; Fast dynamics; Fysik; Physics;

    Sammanfattning : Nanostructured materials promise great advances in diverse and active research fields such as energy harvesting and storage, corrosion prevention and high-density memories. Electrical characterization at the nanometer scale is key to understanding and optimizing the performance of these materials, and therefore central to the progress of nanotechnology. LÄS MER

  4. 3. On efficient and adaptive modelling of friction damping in bladed disks

    Författare :Mohammad Afzal; Leif Kari; Ines Lopez Arteaga; Muzio M Gola; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High cycle fatigue; Friction contact; Jacobian matrix; Shroud contact; Strip damper; Multiharmonic balance method; Contact stiffness; Cyclic symmetry; Nodal diameter; Magnetostrictive actuator; Magnetic field; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : This work focuses on efficient modelling and adaptive control of friction damping in bladed disks. To efficiently simulate the friction contact, a full-3D time-discrete contact model is reformulated and an analytical expression for the Jacobian matrix is derived that reduces the computation time drastically with respect to the classical finite difference method. LÄS MER

  5. 4. Computer Aided Angioplasty : Patient-specific arterial modeling and smooth 3D contact analysis of the stent-balloon-artery interaction

    Författare :Dimitrios Kiousis; Gerhard Holzapfel; Kenneth Runesson; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Contact; continuous surfaces; B-splines; balloon angioplasty; stenting; FEM; Bioengineering; Bioteknik;

    Sammanfattning : Paper A: In this paper, the development and implementation of a contact algorithm based on C2-continuous surface representations is discussed. In 3D contact simulations involving models with arbitrarily curved surfaces (as in the case of vessel walls), the discretization of the contact surfaces by means of facet-based techniques could lead to numerical instabilities and finally loss of quadratic convergence. LÄS MER

  7. 5. Impact loading on concrete structures : a constitutive modelling, finite element analysis, and experimental study of nonlinear wave propagation

    Författare :Larsgunnar Nilsson; Chalmers University of Technology; []
    Nyckelord :experimental study; numerical procedures; plasticity; Nonlinear wave propagation; reinforced concrete; brittle failure; contact-impact; visco plasticity;

    Sammanfattning : .... LÄS MER