A wave flume experiment of wave attenuation through cylinder arrays, mimicking wave damping through a coastal mangrove forest in the Mekong Delta, was performed within a wave flume at Delft University of Technology. A state-of-the-art numerical model mimicking the experiment was constructed in SWASH, and validated using the measured data. Results show that short waves are attenuated very quickly, while infragravity waves. Therefore, long wave attenuation will determine the maximum length scale of the mixing layer's intrusion into the vegetation region. It is suggested that the SWASH model can capture the transformation processes of the wave attenuation observed and measured in the physical model. The wave attenuation rate for a specific mangrove density was presented as a function of the number of wavelengths and the Ursell number. It is suggested that the ratio of incoming and damped wave heights reduces when the Ursell number increases.
