Blar i NTNU Open på forfatter "Holmedal, Lars Erik"
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Note on seabed shear stress beneath bichromatic and bidirectional waves for large bed roughness
Myrhaug, Dag; Simons, Richard R.; Holmedal, Lars Erik (Peer reviewed; Journal article, 2023)The seabed shear stress beneath bichromatic and bidirectional waves is presented. The approach is analytical using the constant time-invariant eddy viscosity representation of Christoffersen and Jonsson (1985) for rough ... -
Numerical investigation of 3D flow around a circular cylinder with forced oscillations
Nygård, Jonas (Master thesis, 2023)Sirkulære sylindere blir brukt i ulike maritime anvendelser som rørledninger og stigerør. Flere eksperimenter utført ved Marintek ble gjennomført av K.H. Aronsen på problemet med en sylinder som svinger både i x- og ... -
Numerical Simulation of Flow around Single and Two side-by-side Square Cylinders with Horizontal Offsets Mounted on the Seafloor
Dai, Yukun (Master thesis, 2016)Computational Fluid Dynamics (CFD) have been applied to obtain essential hydrodynamic quantities and flow behaviors of single and two 2D wall-mounted square cylinders subjected to a uniform turbulent inflow. This is a ... -
Numerical Simulations of Swimming Fish
Mossige, Jon Coll (Master thesis, 2017)A profound understanding of how a fish swims may be used to design innovative propulsion units with higher efficiency than the conventional screw propellers. The gain of such understanding may be aided by the use of ... -
A numerical study of separation and stagnation points for steady and unsteady flow over an elliptic cylinder near a moving wall
Zhu, Jianxun; Holmedal, Lars Erik (Peer reviewed; Journal article, 2021)Flow separation around an elliptic cylinder with an aspect ratio of 0.4 near a moving wall is investigated numerically for Re 2 ½5; 150 with G=D 2 ½0:1; 2 (where G denotes the distance between the cylinder bottom and the ... -
Revisiting statistical properties of surf parameter with characteristic wave parameters for single random waves including spectral bandwidth effects
Myrhaug, Dag; Wang, Hong; Holmedal, Lars Erik; Li, Hongtao (Peer reviewed; Journal article, 2021)Results from a comparative study of the joint distribution of surf parameter and wave period are provided. First, two transformed joint distributions of wave height and wave period are compared. One of the distributions ... -
Sediment Transport in Combined Wave–Current Seabed Boundary Layers due to Streaming
Afzal, Mohammad Saud; Holmedal, Lars Erik; Myrhaug, Dag (Peer reviewed; Journal article, 2021)The sediment transport in the seabed boundary layer due to wave-induced streaming has been investigated for nonzero angle between the current and the waves. The mean sediment transport is a result of interaction between ... -
Seepage effects on bedload sediment transport rate by random waves
Myrhaug, Dag; Holmedal, Lars Erik; Ong, Muk Chen (Journal article, 2014)The mean net bedload sediment transport rate beneath random waves is predicted taking into account the effect of seepage flow. This is achieved by using wave half-cycle bedload sediment transport formulas valid for regular ... -
Stokes drift estimation for deep water waves based on short-term variation of wave conditions
Myrhaug, Dag; Wang, Hong; Holmedal, Lars Erik (Journal article, 2014)The paper provides a simple analytical method which can be used to give estimates of the Stokes drift based on short-term variation of wave conditions. This is achieved by providing bivariate distributions of wave height ... -
Stokes transport in layers in the water column based on long-term wind statistics
Myrhaug, Dag; Wang, Hong; Holmedal, Lars Erik (Journal article; Peer reviewed, 2018)This paper addresses the Stokes transport velocity for deep water random waves in given layers in the water column based on wind statistics, which can be estimated by the simple analytical tool provided here. Results are ... -
Suspended sediments due to random waves including effects of second order wave asymmetry and boundary layer streaming
Myrhaug, Dag; Ong, Muk Chen; Holmedal, Lars Erik (Journal article, 2015)The paper provides a practical stochastic method by which the suspended sediment concentration due to long-crested (2D) and short-crested (3D) nonlinear random waves can be calculated. The approach is based on assuming the ... -
Three-dimensional streaming in sea bed boundary layer
Afzal, Mohammad Saud (Doctoral theses at NTNU;2017:62, Doctoral thesis, 2017)The objective of the work carried out in the present thesis is to obtain new insights into wave- current seabed boundary layers by studying the wave-current interaction for the general case of a non-zero angle between the ... -
Three-dimensional wake transition behind an elliptic cylinder near a moving wall
Zhu, Jianxun; Jiang, Fengjian; Holmedal, Lars Erik (Peer reviewed; Journal article, 2021)In this work, the flow over an elliptic cylinder near a moving wall is investigated for Reynolds numbers less than 150. Here, the ratio between the gap (i.e., the distance between the cylinder and the wall) and the length ... -
Thrust loss due to interaction with ship hull and bottom for ships in shallow waters
Brage Møller-Pettersen (Master thesis, 2022)Målet med denne master avhandlingen er et klart svar på spørsmålet: \emph{Er det en spesifikk effekt, eller kombinasjon av flere som forekommer på grunt vann og forårsaker thrust tap?} Etter et relativt bredt litteratursøk ... -
Tidal and Wind Driven Boundary Layer Flow in Coastal Zones
Andersen, Ingrid Rolland (Master thesis, 2018)The objective with this thesis is to investigate the start-up of a pure wind driven flow, and the effect of an suddenly increasing wind (starting from zero wind speed) on a tidally driven flow. This is done by performing ... -
Tidal boundary layer flow over a flat bottom with vegetation
Holmemo, Marius (Master thesis, 2016)A numerical k-epsilon model has been modified to account for the presence of submerged vegetation. The code has been successfully validated and run against tidal current measurement. The results looks promising. Especially ... -
VIV suppression in 2D circular cylinders through staggered grooves: A numerical investigation at low Reynolds number
Sinha, Apoorva (Master thesis, 2023)Vortex-induced vibration (VIV), a ubiquitous fluid-structure interaction phenomenon, plays a crucial role in the operational safety and longevity of various engineering structures subjected to fluid flow, such as marine ... -
Vortex dynamics and flow patterns in a two-dimensional oscillatory lid-driven rectangular cavity
Zhu, Jianxun; Holmedal, Lars Erik; Wang, Hong; Myrhaug, Dag (Peer reviewed; Journal article, 2020)The vortex dynamics in a two-dimensional oscillatory lid-driven cavity with depth-to-width ratio 1:2 has been investigated, covering a wide range of Reynolds numbers and Stokes numbers where this flow is known to be in the ... -
Wave-induced current for long-crested and short-crested random waves
Myrhaug, Dag; Holmedal, Lars Erik (Journal article; Peer reviewed, 2014)This paper provides a simple analytical tool which can be used to calculate the wave-induced current beneath long-crested (2D) and short-crested (3D) random waves. The approach is based on assuming the waves to be a ...