Sökning: "Contact condition"

Visar resultat 1 - 5 av 154 avhandlingar innehållade orden Contact condition.

  1. 1. Towards Model-Based Condition Monitoring of Railway Switches and Crossings

    Författare :Marko Milosevic; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sleeper void; Switches crossings; condition indicators; embedded sleeper accelerometer; multi-body simulations; dynamic vehicle–track interaction; MBS; S C; wheel–rail contact forces; condition monitoring; crossing rail geometry; displacement reconstruction.; model calibration;

    Sammanfattning : Railway switches and crossings (S&C, turnouts) connect different track sections and create a railway network by allowing for trains to change between tracks. This functionality comes at a cost as the load-inducing rail discontinuities in the switch and crossing panels cause much higher degradation rates for S&C compared to regular plain line track. LÄS MER

  3. 2. Condition monitoring of railway vehicles : a study on wheel condition for heavy haul rolling stock

    Författare :Mikael Palo; Thomas Robertsson; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Drift och underhållsteknik; Operation and Maintenance;

    Sammanfattning : A railway is an energy efficient mode of transport as it uses the low resistance contact between wheel and rail. This contact is not frictionless and causes wear on both surfaces. The wheel-rail guidance is made possible by the shapes of wheel and rail profiles. LÄS MER

  4. 3. Rough surfaces in contact : artificial intelligence and boundary lubrication

    Författare :Marco Rapetto; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Machine Elements; Maskinelement;

    Sammanfattning : Interacting surfaces are found in mechanical systems and components. Since engineered surfaces are not perfectly smooth, only a fraction of the nominal surface area is actually in contact. This fraction is denoted as the real area of contact, Ar, and is formed by the sum of the contact spots between the two touching surfaces. LÄS MER

  5. 4. Modelling of Moving Contact Lines in Two-Phase Flows

    Författare :Hanna Holmgren; Gunilla Kreiss; Stefan Turek; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computational fluid dynamics; Two-phase flow; Contact lines; Scientific Computing; Beräkningsvetenskap;

    Sammanfattning : Moving contact line problems appear in many natural and industrial processes. A contact line is formed where the interface between two immiscible fluids meets a solid wall. Examples from everyday life include raindrops falling on a window and water bugs resting on water surfaces. LÄS MER

  7. 5. Congenital cataract and contact lenses

    Författare :Sara De Lima; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :;

    Sammanfattning : Purpose: Having a child with congenital cataract is associated with a huge responsibility for the parents in terms of the outcome of their child’s visual development. If the cataract is not removed the condition will lead to lifelong visual impairment and the surgery is preferably preformed within the first three months of life. LÄS MER