Browsing NTNU Open by Author "Akselsen, Andreas Holm"

Now showing items 1-6 of 6

    • Designing vortices in pipe flow with topography-driven Langmuir circulation 

      Ellingsen, Simen Andreas Ådnøy; Akselsen, Andreas Holm; Chan, Leon (Peer reviewed; Journal article, 2021)
      We present direct numerical simulation of a mechanism for creating longitudinal vortices in pipe flow, compared with a model theory. By furnishing the pipe wall with a pattern of crossing waves, secondary flow in the form ...

    • Efficient Numerical Methods for Waves in One-Dimensional Two-Phase Pipe Flows 

      Akselsen, Andreas Holm (Doctoral thesis at NTNU;2016:207, Doctoral thesis, 2016)
      This thesis is aimed at improving simulation efficiency for stratified-wavy gasliquid flows. Towards this goad, the simpler nature of incompressible two-phase flows is utilized for predicting hydraulic wave dynamics, ...

    • Langmuir-type vortices in wall-bounded flows driven by a criss-cross wavy wall topography 

      Akselsen, Andreas Holm; Ellingsen, Simen Andreas Ådnøy (Peer reviewed; Journal article, 2020)
      We investigate a mechanism to manipulate wall-bounded flows whereby wave-like undulations of the wall topography drives the creation of bespoke longitudinal vortices. A resonant interaction between the ambient vorticity ...

    • Sheared free-surface flow over three-dimensional obstructions of finite amplitude 

      Akselsen, Andreas Holm; Ellingsen, Simen Andreas Ådnøy (Journal article; Peer reviewed, 2019)
      When shallow water flows over uneven bathymetry, the water surface is modulated. This type of problem has been revisited numerous times since it was first studied by Lord Kelvin in 1886. Our study analytically examines ...

    • Simulation of Unstable Two-phase Flows in Long Risers 

      Akselsen, Andreas Holm (Master thesis, 2012)
      The principles of the object oriented slug tracking schemes at EPT (Department of Energy and Process Engineering, NTNU) have been developed and discussed in some detail.Simple bench-mark testing revealed that the LASSI ...

    • Weakly nonlinear transient waves on a shear current: ring waves and skewed Langmuir rolls 

      Akselsen, Andreas Holm; Ellingsen, Simen Andreas Ådnøy (Journal article; Peer reviewed, 2019)
      We investigate the weakly nonlinear dynamics of transient gravity waves at infinite depth under the influence of a shear current varying linearly with depth. The shear field makes this problem three-dimensional and rotational ...