합류부에서의지류의합류각, 지류와본류의유량비에추가하여, 본류준설에의한하상고불일치에따른다양한양상의 분리구역의특성을CCHE2D 모형을사용하여분석하였다. 분리구역은지류가합류되어진직후단면에서의유속이0(영)인 경계로정의하였다. 합류각30° 이하에서는분리구역이형성되지않았다. 유량비와합류각증가에따른분리구역의크기는 일반적으로 증가하는 양상으로 나타났다. 준설 깊이비 증가에 따른 분리구역의 크기는 합류부 수용체의 증가에 기인한 지류에서의상대적인 운동량의감소로인하여감소되었다. 유량비와합류각의변화에따른분리구역의수축지수를규명하 였고, 통수기능의저하에따른배수영향을확인하였다. 합류각, 유량비, 준설깊이비에따른분리구역의형상지수의관계식 을 제안하였다.

The diverse patterns of separation zone according to the marked bed discordance by dredging at confluence in addition to the confluence angle of tributary and discharge ratio between tributary and main channels have been analyzed by CCHE2D model simulation. The separation zone is defined by inside of zero velocity boundary at down-stream of confluence. The separation zone dose not formed at the 30° of confluence angle of tributary. The size of separation zone increases as the discharge ratio and confluence angle increase in general. The separation zone decreases as the dredging depth increases which shows the relative momentum reduction compared by the flow volume increasing by dredging at confluence. The contraction factor with the variation of confluence angle and discharge ratio has been investigated and confirmed the corresponding conveyance decreasing results in backwater effect. The regression equation of shape factor with confluence angle and discharge and dredging depth ratios has been suggested.

• 최흥식(상지대학교 건설시스템공학과 교수) | Choi, Heung Sik 교신저자
• 모선재(㈜창설, 수자원부 주임) | Mo, Sun Jea