Numerical study on generation mechanism of rip current at Haeundae beach, Korea

Abstract

Haeundae beach is one of the most famous tourist attractions in Busan, Korea and, every year, millions of people have been visiting the beach. Recently, however, a rip current accident has been continuously observed in the middle of the beach and rescue workers covering Busan’s beaches have been on the highest alert for repeated rip currents. For example, more than 500 people was swept away by a strong channel of water flowing seaward from the shore and rescued after being dragged into deeper waters in 2013. Fortunately, no casualties were reported but the authorities said, given that the ideal weather conditions for rip currents are persisting, they could occur again at any time not only at Haeundae but also at other beaches. There have been some researches to identify generation mechanism of rip currents at Haeundae beach. Among them, an interesting numerical study inferred that a known mechanism of generating rip current due to the nodal line area of honeycomb-pattered wave crest was one of the significant factors of rip current occurrences of Haeundae beach. They conducted numerical experiments of nearshore circulation at Haeundae beach using a nonlinear Boussinesq equation model to confirm their hypothesis. In this study, we performed numerical experiments at Haeundae beach to identify generation mechanism of rip currents following their hypothesis. A well-known Boussinesq equations solver, FUNWAVE-TVD was emplch and rescue workers covering Busan’s beaches have been on the highest alert for repeated rip currents. For example, more than 500 people was swept away by a strong channel of water flowing seaward from the shore and rescued after being dragged into deeper waters in 2013. Fortunately, no casualties were reported but the authorities said, given that the ideal weather conditions for rip currents are persisting, they could occur again at any time not only at Haeundae but also at other beaches. There have been some researches to identify generation mechanism of rip currents at Haeundae beach. Among them, an interesting numerical study inferred that a known mechanism of generating rip current due to the nodal line area of honeycomb-pattered wave crest was one of the significant factors of rip current occurrences of Haeundae beach. They conducted numerical experiments of nearshore circulation at Haeundae beach using a nonlinear Boussinesq equation model to confirm their hypothesis. In this study, we performed numerical experiments at Haeundae beach to identify generation mechanism of rip currents following their hypothesis. A well-known Boussinesq equations solver, FUNWAVE-TVD was empl