Analysis of wind effects on river surface velocity and evaluation of wind correction coefficient applicability

Sinjae Lee; Seokgeun Park; Bokjin Jang; Geunsoo Son

doi:10.3741/JKWRA.2026.59.9.1061

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2026 Vol.59, Issue 9 Preview Page Next Page

Analysis of wind effects on river surface velocity and evaluation of wind correction coefficient applicability 하천 표면유속의 바람영향 분석 및 바람보정계수 적용성 평가

30 September 2026. pp. 1061-1070

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Abstract

As the use of non-contact surface velocimeters for river discharge measurement has increased, it has become increasingly important to consider external factors affecting surface velocity. Among these factors, wind is a major contributor to variations in surface velocity and may introduce errors in velocity and discharge measurements if not properly accounted for. This study investigated the effect of headwind conditions on river surface velocity through experiments conducted in an experimental channel. The results showed that the change in surface velocity corresponded, on average, to 3.3% of the wind speed measured at a height of 10 m above the water surface, yielding a wind correction coefficient of 0.033. The derived wind drift coefficient was applied to the Hongcheon Station (Hongcheon Bridge) on the Hongcheon River, where an automatic discharge measurement system based on a radar surface velocimeter is installed. Surface velocities measured by the radar surface velocimeter were corrected using the proposed coefficient, and the mean velocities estimated by the Index Velocity Rating Curve Method (IVRC) were compared with those derived from the Stage-Discharge Rating Curve (HQRC). As a result, the RMSE decreased by 25%, from 0.04 m/s to 0.03 m/s. In addition, the temporal variation of the corrected mean velocity showed better agreement with the HQRC-based mean velocity than that of the uncorrected velocity. These results demonstrate the importance of accounting for wind effects in surface-velocity-based discharge measurements and confirm the applicability of the proposed wind correction coefficient under field conditions.

Keywords

Surface velocity

Wind effect

Wind correction coefficient

Index velocity rating curve method

Mean velocity

최근 비접촉식 표면유속계를 이용한 하천 유량측정이 확대됨에 따라 표면유속에 영향을 미치는 외부 요인에 대한 고려가 중요해지고 있다. 특히 바람은 표면유속을 변화시키는 주요 인자로, 이를 고려하지 않을 경우 유속 및 유량측정 오차를 유발할 수 있다. 본 연구에서는 실험수로를 이용하여 역풍 조건에서 바람이 표면유속에 미치는 영향을 분석하였다. 그 결과 표면유속 변화량은 수면 기준 10 m 높이 풍속의 평균 3.3%에 해당하는 것으로 나타났으며, 이에 따른 바람보정계수는 0.033으로 산정되었다. 산정된 바람보정계수는 레이더 표면유속계 기반 자동유량측정시스템이 구축된 홍천강 홍천군(홍천교) 지점에 적용하였다. 레이더 표면유속계로 측정한 표면유속에 바람보정계수를 적용한 후 지표유속법(IVRC)으로 산정한 평균유속을 수위-유량관계곡선(HQRC) 기반 평균유속과 비교한 결과, RMSE는 0.04 m/s에서 0.03 m/s로 25% 감소하였다. 또한 보정 후 평균유속의 변동 경향은 HQRC 기반 평균유속과 더욱 잘 일치하는 것으로 나타났다. 이러한 결과는 표면유속 기반 유량측정에서 바람영향 보정의 필요성을 보여주며, 본 연구에서 산정한 바람보정계수의 현장 적용 가능성을 확인할 수 있었다.

키워드

표면유속

바람영향

바람보정계수

지표유속법

평균유속

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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 : 59
No :9
Pages :1061-1070
Received Date : 2026-06-19
Revised Date : 2026-07-06
Accepted Date : 2026-07-08
DOI :https://doi.org/10.3741/JKWRA.2026.59.9.1061

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

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