Comparison of Local Scour around Pipeline Caused by Waves and Steady Currents

doi:2011.25.2.21

J. Ocean Eng. Technol. > Volume 25(2); 2011 > Article

J. Ocean Eng. Technol. 2011;25(2):21-28.
DOI: https://doi.org/10.5574/KSOE.2011.25.2.021

Kim Kyoung-Ho,Oh Hyoun-Sik

Dept. of Civil Engineering Chungbuk National University,Dept. of Civil Engineering Chungbuk National University

파랑 및 정상흐름에 의한 해저관로 주변의 국부세굴 특성 비교

김경호,오현식

충북대학교 토목공학과,충북대학교 토목공학과

Keywords: Local scour hole, Scour width, Scour depth, Shallow water, Fr number, KC number, Pipeline

핵심용어: 국부 세굴공, 세굴폭, 세굴심, 천해, Fr 수, KC 수, 관로

Abstract

The primary purpose of the present study was to investigate the mechanism causing scour around a pipeline placed on the seabed in a shallow water zone. Such submarine pipelines are usually exposed to currents and waves. The present experiments made estimates for each different flow type. The scour width and depth in the equilibrium scour phase were analyzed by non-dimensional parameters. The experiment in this study considered various parameters: pipe diameters, wave periods, wave heights, and current velocities. Using the experimental results, the correlations of scour width, scour depth, and main non-dimensional parameters such as the Fr number and KC number were analyzed. In the case of steady currents, the scour hole was closely related to the bottom velocity, while the scour hole in waves showed a relatively low correlation to the bottom velocity because when exposed to waves the scour hole was restricted according to the movement distance of the water particles during a wave period. However, the scour width under a steady current was not limited because vortex shedding was well developed from having enough time and distance.