<%namespace name="tools" file="tools.tex"/>
<%! import os %>

\citet{Boers1996} performed experiments with irregular waves in the physical wave flume at Delft University of Technology with a length of 40 meters and a width of 0.8 m. The flume is equipped with a hydraulically driven, piston type wave generator with second-order wave generation and Active Reflection Compensation. Boers ran waves over a concrete bar-trough beach, which was modelled after the Delta Flume experiments. He ran three different irregular wave conditions, but in this report we will focus on case 1C, a Jonswap spectrum with $H_{m,0}$ = 0.1m and $T_p$ = 3.3s. The surface elevation was measured in 70 locations shown in \autoref{fig:gaugeloc}.

${tools.image(os.path.join(input_path, 'Boers_1C/surfbeat/'), 'gaugeloc.png', 'Locations of surface eleveation measurements')}
                        
The comparison between the model and the data for the wave height transformation of the short waves and the long waves (defined as waves with a frequency greater than $f_p/2$ and less than $f_p/2$, respectively) is shown in \autoref{fig:Boers_1C_surfbeat_figSpecCorrect}. 

The red dashed line and triangles indicate the short wave height transformation. The blue line and circles indicate the mean (steady) set-up. The dotted red line and upside-down traiangles indicate the total (incoming and reflected) low frequency wave.

The observational data is separated into incoming and reflected long wave components using an array of wave gauges \citep{Bakkenes2002} and the numerical data has been separated into two components using co-located surface elevation and velocity information.

${tools.image('Boers_1C/surfbeat/', 'figSpecCorrect.png', 'Wave height transformations during Boers 1C experiment for XBeach in surfbeat mode.')}
${tools.image('Boers_1C/non-hydrostatic/', 'fig.png', 'Wave height transformations during Boers 1C experiment for XBeach in non-hydrostatic mode.')}

% if interpret:

The model performs reasonably well against the data for this well-measured but complex case. The high frequency wave transformation compares well with the measurements, except for details around the breakpoint. The steady water level setup is well-predicted, except in the trough region (x=21-25 m). The low frequency wave height is slightly overpredicted in the shoaling zone (up to the breakpoint) and stays too large after that.

% endif