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Numerical study for classifying generation types of rip currents at the beaches of the East Sea coast

수치모의를 통한 동해안 해수욕장의 이안류 발생 형태 분류 연구

  • Choi, Junwoo (Coastal Research Laboratory, Department of Hydro Science and Engineering Research, Korea Institute of Civil Engineering & Building Technology)
  • 최준우 (한국건설기술연구원 수자원하천연구본부)
  • Received : 2022.07.06
  • Accepted : 2022.08.09
  • Published : 2022.09.30

Abstract

Recently rip currents are frequently observed in the summer at the beaches located along the East Sea coast. To understand the generation types of rip currents occurred at the Ease Sea beaches, numerical simulations of rip currents over the topographies of the Sokcho, Naksan, Gyeongpo, Mangsang beaches were performed by using a Boussinesq-type wave and current model, FUNWAVE. The offshore and nearshore topographically-controlled rip currents and the transient rip currents were well reproduced due to the alongshore non-uniformities involving the phase interaction effects. This study looked over the generation types of rip currents to occur at the beaches with complicated field bathymetries.

최근 동해안 해수욕장에서도 여름철 해수욕 기간에 이안류가 자주 관찰되고 있다. 우리나라 동해안에 위치한 해수욕장들에서 발생하는 이안류의 원인 특성을 수치모의 결과를 이용하여 검토하였다. 속초, 낙산, 경포대, 망상 해수욕장 앞바다의 수심자료를 이용하여 Boussinesq 방정식을 지배 방정식으로 하는 FUNWAVE 모형으로 수치모의를 수행하였다. 각 해수욕장 앞바다 지형, 샌드바 형성 및 입사파 특성 등의 영향으로 변형되는 위상의 상호작용을 포함한 파의 횡방향 비균등성에 의해 발생하는 이안류가 잘 재현되었다. 그 결과를 기반으로 각 해수욕장에서 발생 가능한 이안류의 종류를 기술하였다.

Keywords

Acknowledgement

본 연구는 해양수산부 국립해양조사원의 "실시간 이안류 감시체계 확대 및 서비스" 사업의 지원으로 수행되었습니다.

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