A numerical study on rip currents at the Haeundae coast changed after the beach nourishment

Junwoo Choi

doi:10.3741/JKWRA.2022.55.9.669

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2022 Vol.55, Issue 9 Preview Page Next Page

Research Article

A numerical study on rip currents at the Haeundae coast changed after the beach nourishment 양빈 후 지형변화에 따른 해운대 이안류 수치모의

30 September 2022. pp. 669-678

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Abstract

The Haeundae beach and coast suffered synthetical dramatic changes especially in the nearshore topography by the beach nourishment project (i.e., 2013-2015). A previous study showed the rip current characteristics were changed according to the topographical change in terms of their magnitudes and likelihoods through numerical simulations using the FUNWAVE model. The magnitude and likelihood of rip currents decreased because the surfzone width decreased just after the beach nourishment. In this study, however, numerical simulations of the Haeundae rip currents were performed by using the 2017- and 2020-surveyed topographies changed for several years after the beach nourishment. From the simulation results using the topographies surveyed before and after the beach nourishment, it was found that the magnitude and likelihood of rip currents increased due to its increasing surfzone width in 2017 and 2020 and they might be increasing larger than those before the beach nourishment.

Keywords

Haeundae

Rip current

Beach nourishment

Numerical simulation

FUNWAVE

연안정비사업으로 추진된 해운대 해수욕장의 대규모 양빈(2013~2015)으로 해운대 해변의 해안선 및 수심지형에 급한 인위적 변동이 있었다. 기존 연구에서는 양빈 직, 전후의 수심지형을 입력 조건으로 Boussinesq 방정식 모형인 FUNWAVE를 이용하여 수치모의를 수행, 수심지형 변화에 따른 이안류 발생 특성을 분석하였다. 양빈 직후 쇄파대 폭의 감소로 이안류의 강도 및 발생정도가 감소하였다. 본 연구에서는 대규모 양빈 후 수년이 지난 2017년 및 2020년에 다시 측량된 수심지형을 이용하여 동일한 조건으로 수치모의를 수행하여 결과를 제시하였다. 그리고 양빈 전 및 직후, 그리고 수년이 지난 후의 해운대 이안류를 비교하였다. 시간이 지남에 따라 단면경사가 완만해 지고 쇄패대 폭이 증가되어 이안류의 강도와 발생정도가 다시 증가하고 있다고 판단된다.

키워드

해운대

이안류

양빈

수치모의

FUNWAVE

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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 : 55
No :9
Pages :669-678
Received Date : 2022-07-18
Revised Date : 2022-08-22
Accepted Date : 2022-08-29
DOI :https://doi.org/10.3741/JKWRA.2022.55.9.669

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

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