Sediment Resuspension Induced By Wave Breaking In The Nearshore Zone

Breaking waves play a pivotal role in sediment resuspension events within the nearshore zone of coastal regions. This can result in significant sediment transport and beach transformation. This study explores the role of breaking waves in sediment resuspension within the nearshore zone of coastal regions. Laboratory experiments will be conducted to calculate the velocity fields and shear stresses associated with plunging waves at different stages of wave breaking. The experiments incorporate a physical beach model setup in a 15 m long  wave flume. Using a mechanical wave generator, uniform solitary waves will be generated in the wave flume for varying beach profiles. The experimental arrangement is akin to the arrangement depicted in the figure below.

Particle Image Velocimetry (PIV) will be used to measure the instantaneous velocity fields in a two-dimensional (2D) plane at the various stages of wave breaking by selecting different Field of Views (FOVs). A phase averaged velocity profile for the flow under a plunging breaker will be derived from the PIV images.  The results of this investigation will be used to improve sediment transport parameterisation in numerical/computational/deterministic models. The breaking process of a small plunging wave was recorded in the laboratory and can be seen in the video below.

 

Ayesha Mahomedy

BScEng (Civil)