Search for dissertations about: "transient contact"

Showing result 1 - 5 of 71 swedish dissertations containing the words transient contact.

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

   Author : Andreas Draganis; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thermomechanical coupling; finite element method; transient analysis; arbitrary Lagrangian--Eulerian; rolling contact; frictional contact;

   Abstract : 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. READ MORE

4. 2. Transient elastohydrodynamic lubrication : Effects of geometry, surface roughness, temperature, and plastic deformation

   Author : Tobias Hultqvist; Roland Larsson; Pär Marklund; Wassim Habchi; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements;

   Abstract : The urgent need to reduce greenhouse gas emissions in combination with an increased use of sustainable energy resources have led to immense efforts on improving energy efficiency of mechanical systems. Consequently, modern machine elements are typically lubricated with low viscosity oils and designed to endure an increasingly high power density. READ MORE

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

   Author : Astrid Pieringer; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wheel rail interaction; railway noise; roughness; time domain; frictional instability; discrete irregularities; transient contact; non-Hertzian contact;

   Abstract : 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. READ MORE

6. 4. Numerical simulation of thermomechanical rolling contact using an arbitrary Lagrangian-Eulerian formulation

   Author : Andreas Draganis; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rolling contact; finite element method; thermomechanical analysis; arbitrary Lagrangian--Eulerian;

   Abstract : In the endeavour to further the understanding of thermomechanical rolling contact, numerical simulations serve as an important complement to laboratory and full-scale testing. In the development of numerical simulation methods, the challenge is to enhance predictive capabilities while keeping computational efforts reasonable. READ MORE

7. 5. On wear transitions in the wheel-rail contact

   Author : Sundh Jon; Ulf Olofsson; Staffan Jacobsson; KTH; []
   Keywords : Wear transitions; Wheel; Rail; Wear regime; Wear mechanism; Mechanical engineering; Maskinteknik;

   Abstract : Wear transitions in the wheel–rail contact are of increasing interest since the general trend in railway traffic is toward increased velocities and axle loads. Curving increases the risk of flanging, causing the contact to change from an almost pure rolling wheel tread–rail head contact to more of a sliding wheel flange–rail gauge contact on the high rail in curves. READ MORE