Impact of harbor navigation channels on waves: A numerical modelling guideline

This study presents an intercomparison of a SWAN and SWASH wave model and 3D laboratory experiments for an existing navigation channel towards a harbor. Results show that the spectral refraction model SWAN underestimates the wave conditions in the channel and at the lee side of the channel especially - for longer waves travelling under a small...

Impact of Harbor Navigation Channels on Waves: A Numerical Modelling Guideline

This study presents an intercomparison of a SWAN and SWASH wave model and 3D laboratory experiments for an existing navigation channel towards a harbor. Results show that the spectral refraction model SWAN underestimates the wave conditions in the channel and at the lee side of the channel especially - for longer waves travelling under a small...

Propagation of wave groups over bathymetry using a variational Boussinesq model

Modified boundary conditions and field equations for a 2D surf beat model

This progress report refers to work done at the Fluid IVlechanics Section within the framework of the Netherlands Centre for Coastal Research (NCK). In the coastal zone the long wave motion may contribute significantly to the morpho-dynamics, due to its strong correlation with the short wave motion by surf beat. Also wave-group induced edge...

Characteristics of phase-averaged equations for modulated wave groups

The project concerns the influence of long waves on coastal morphology. The modelling of the combined motion of the long waves and short waves in the horizontal plane is done by phase-averaging over the short wave motion and using intra-wave modelling for the long waves, see e.g. Roelvink (1993). The evolution of the long-wave motion and the...

Secondary circulation of the flow due to waves - Laser-doppler flow measurements following or opposing a current

Previous measurements (e.g., Klopman, 1994) have shown that in the centre-line of the flume the mean horizontal velocity profile in waves fol/owing the current bends back in the upper region of the water column compared to the current alone case. For waves opposing the current the opposite behaviour was found . In order to explain this behaviour...

Secondary circulation of the flow due to waves and current: Laser-Doppler flow measurements for waves following or opposing a current

Vertical structure of the flow due to waves and currents, part 2: Laser-Doppler flow measurements for waves following or opposing a current

Vertical structure of the flow due to waves and currents - Laser-doppler flow measurements for waves following or opposing a current

Changes in the mean horizontal-velocity profile in combined wave-current motion, outside the bottom boundary-layer, are essential for the correct prediction of cross-shore sediment transport outside the surf zone and the transport of dissolved matter, e.g. Klopman (1992). To be able to verify mathematical and numerical models (see Klopman, 1992)...

Laboratory wave generation: A second-order theory for regular and irregular waves in wave channels

The correct generation of a second order wave field in a laboratory wave tank is of importance in several experimental investigations, particularly those of nonlinear evolutions and sediment transport. In the present work, which was carried out under the MLTP (medium long-term planning) of DELFT HYDRAULICS for improving experimental techniques,...

A new method for the generation of second-order random waves

For the generation of second-order random waves in a flume the control signal for the wave board has to be correct up to second order. An expression for this control signal is derived with the perturbation method of multiple scales. It is much less complex and requires less computation time than the expressions obtained from the full second...

Extreme waves and wave loading in shallow water

As an alternative to a more or less standard derivation procedure for design wave heights in relatively shallow water, two improvements of the procedure are suggested which lead to less conservative results. These improvements are based on observations of shallow water effects on both the decay of total wave energy density and on the extreme...

Onderdrukken van lek naar zijlobben bij het berekenen van auto- en kruisspectra mb.v. fast fourier transforms

Bij het bepalen van auto- en kruisspectrale vermogensdichtheidsfunklies (in het vervolg van deze notitie: spectra) van tijdreeksen ult een meetreeks van beperkte duur, onstaat in het algemeen lek van vermogensdichtheid bij een bepaalde frequentie naar andere frequenties. Dit wordt veroorzaakt door het feit, dat als het signaal periodiek wordt...

Apparatus for Force and Pressure Measurement on Circular Cylinders