Periodically moving boundary; An extension to model breaking waves in surf and swash zones

Most of the processes in the nearshore zone are extermely dynamic, wave breaking is a important phonemenon that orifinates many of them. It not only absorbs wave energy but also inserts turbulence into the fluid, which generates currents in the nearshore zone. Breaking waves, when they reach to yhe shore, still have enough energy to climb up the beach, till loosing all their energy and then retyrn back to the sea under gravity force. This story will be repeated frequently which forms the shoreline boundary, moving back and forth as waves meet the shore.