Sökning: "simulations"

Visar resultat 21 - 25 av 4628 avhandlingar innehållade ordet simulations.

  1. 21. Correlation between Track Irregularities and Vehicle Dynamic Response Based on Measurements and Simulations

    Författare :Tomas Karis; Mats Berg; Jens Nielsen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; track irregularities; vehicle response; wheel–rail force; axle box acceleration; Dynotrain; Gröna Tåget; multi-body system; simulations; spårlägesfel; fordonsrespons; hjul–räl-krafter; axelboxacceleration; Dynotrain; Gröna Tåget; flerkroppssystem system; simuleringar; Järnvägsgruppen - Fordonsteknik; Järnvägsgruppen - Fordonsteknik; Vehicle and Maritime Engineering; Farkostteknik; Järnvägsgruppen - Infrastruktur; Järnvägsgruppen - Infrastruktur;

    Sammanfattning : Deviations from the design track geometry are called track irregularities, which are a main excitation mechanism in the track–vehicle dynamic system, and very important to monitor and maintain to have trac on a line run safely and comfortably. Especially during vehicle acceptance testing, it is important that a new vehicle behaves close to design predictions and within limit values, thus it is important to be able to describe track irregularities in a consistent way. LÄS MER

  2. 22. Engine Encapsulation for Increased Fuel Efficiency of Road Vehicles

    Författare :Blago Minovski; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; coupled simulations; powertain cooling systems; warm-up; 1D simulations; thermal engine encapsulation; cool-down; fuel consumption; numerical analysis; 3D CFD simulations;

    Sammanfattning : Thermal engine encapsulation is an increasingly popular design choice, which insulates the engine from the external environment and retains heat in the engine after it is turned off. This decelerates motor cool-down and increases the probability for high initial temperature at a subsequent engine start, resulting in shorter warm-up and reduced friction between engine parts. LÄS MER

  3. 23. Mechanical braking systems for trains: A study of temperatures, fatigue and wear by experiments and simulations

    Författare :Mandeep Singh Walia; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; tread brakes; experiments; temperatures; disc brakes; wear; Railway braking; simulations; fatigue;

    Sammanfattning : Increased demand for shorter travel times, higher axle loads, increased volumes and increased punctuality of railway traffic calls for a better design and management of the railway subsystems. The present thesis deals with aspects of mechanical friction brakes, in the form of tread brakes and disc brakes. LÄS MER

  4. 24. Coupled Simulations of Cooling and Engine Systems for Unsteady Analysis of the Benefits of Thermal Engine Encapsulation

    Författare :Blago Minovski; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Oil system; Cooling system; Drive cycle; CFD simulations; Fuel consumption; Engine encapsulation; 1D simulations;

    Sammanfattning : A well-designed engine encapsulation can extend engine cool-down time significantly - on the order of 500 - 700%. This is expected to have a sensitive influence on the fuel consumption due to the increased probability for high oil temperatures at the following engine start, reduced length of the initial warm-up period and consequently, reduced friction losses. LÄS MER

  5. 25. Structure, Dynamics and Thermodynamics of Liquid Water : Insights from Molecular Simulations

    Författare :Kjartan Thor Wikfeldt; Lars G. M. Pettersson; Francesco Sciortino; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Liquid water; supercooled water; diffraction; structure modeling; molecular dynamics; x-ray spectroscopy; EXAFS; SAXS; Physics; Fysik; Theoretical Physics; teoretisk fysik;

    Sammanfattning : Water is a complex liquid with many unusual properties. Our understanding of its physical, chemical and biological properties is greatly advanced after a century of dedicated research but there are still many unresolved questions. LÄS MER