Laboratory experiment of evolution of rip current according to the duration of successive ends of breaking wave crests

Junwoo Choi

doi:10.3741/JKWRA.2021.54.1.39

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2021 Vol.54, Issue 1 Preview Page Next Page

Research Article

Laboratory experiment of evolution of rip current according to the duration of successive ends of breaking wave crests 연속 쇄파선 끝단 지속시간에 따른 이안류 발달 수리실험 연구

31 January 2021. pp. 39-48

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Abstract

The experiment of rip current at successive ends of breaking wave crests was conducted in a laboratory wave basin, and its time-varying evolution according to incident wave durations was observed by using ortho-rectified images. The experiment utilized the generation of a quasi nodal line of the honeycomb-pattern waves (i.e., intersecting wave trains) formed by out-of-phase motion of two piston-type wave makers arranged in the transverse direction, instead of the original honeycomb pattern waves which are generated when two wave trains propagate with slightly different wave directions. The particle moving distance and velocity caused by the rip current were measured by using the particle tracking technique. As a result, the rip current was survived for a while even without incident waves after its generation due to several successive ends of wave crests, and it moved the particles further out to sea.

Keywords

Laboratory experiment

Breaking wave crests

Duration of incident waves

Unsteady rip current

Ortho-rectified image

Particle tracking

연속된 쇄파 파봉선 끝단사이로 발달하는 이안류를 수리실험을 통해 재현하고 입사파 지속시간의 변화에 따른 이안류 발달 특성을 정사보정 영상을 통해 관찰하였다. 서로 다른 두 협각의 파랑 중첩에 의해 생성되는 벌집구조 파를 재현하는 대신에 조파장치를 횡방향 두 그룹으로 나누어 역 위상으로 구동시켜 규칙파를 조파하므로 유사 벌집구조 파형을 생성하여 실험을 수행하였다. 수리 실험에서 재현된 이안류의 생성과 발달 과정을 관찰하기 위해 정사보정 영상기반 입자 추적 기법을 사용하였으며, 이를 통해 이동거리와 속도를 관측하였다. 연속된 쇄파선 끝단이 해안으로 입사하여 이안류가 생성되지만, 이안류가 생성된 후 파랑이 더 이상 입사되지 않아도 상당시간 동안 이안류가 발달하여 입자들이 외해로 이동하는 것을 확인하였다.

키워드

수리실험

연속 쇄파선 끝단

입사파 지속시간

이안류

정사보정 영상

파티클 추적

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Information

Publisher :KOREA WATER RESOURECES ASSOCIATION
Publisher(Ko) :한국수자원학회
Journal Title :Journal of Korea Water Resources Association
Journal Title(Ko) :한국수자원학회 논문집
Volume : 54
No :1
Pages :39-48
Received Date : 2020-11-05
Revised Date : 2020-11-23
Accepted Date : 2020-11-23
DOI :https://doi.org/10.3741/JKWRA.2021.54.1.39

Journal of Korea Water Resources Association ISSN:2799-8746(Print) 2799-8754(Online) 한국수자원학회 논문집

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