점착성 변화에 따른 미세입자의 퇴적거동 = Depositional Behavior of Fine-Grained Particles with Varying Cohesiveness

다국어 초록 (Multilingual Abstract)

The purpose of this paper is to examine the effect of their cohesiveness on the deposition behavior of fine-grained sediments with varying cohesiveness, through laboratory experiments. Laboratory studies are realized in a small annular flume with a free water surface, where the flow is driven by the rotating inner cylinder. Sediment material is using silica particle, which is the main mineral components of clay that affect sedimentation. Results show that the deposition rate of silica increases more rapidly at pH4.2 than at pH6.8 with decreasing bed shear stress due to the effect of the cohesiveness. Silica particle is not deposited above the bed shear stress of 0.022 N/m 2 in distilled water. The minimum shear stress of silica occurs under the bed shear stress of 0.008 N/m 2 . Thus, the settling velocity ranged from approximately 0.0003~0.006 mm/s under variable pH value and shear stress.

국문 초록 (Abstract)

본 논문의 목적은 실험을 통해 점착성 변화에 따른 미세유사의 퇴적거동을 연구하는 것이다. 실험연구는 내부 실린더의 회전에 의해흐름이 구동되며 자유 수면이 존재하는 소형환형수조에서 실시되었다. 유사재료는 퇴적에 영향을 주는 점토의 주성분인 실리카 미립자가 사용되었다. 점착성영향 때문에 바닥전단응력이 감속할 경우 실리카의 퇴적률이 pH6.8보다 pH4.2에서 빠르게 증가하는 결과를나타낸다. 실리카의 입자의 경우 증류수에서 바닥전단응력 0.022 N/m 2이상일 때 퇴적이 발생하지 않았다. 실리카의 최소전단응력은바닥전단응력 0.008 N/m 2이하에서 나타났다. 이때 침강속도는 pH와 전단응력이 변화할 경우 0.0003~0.006 mm/s범위이다.

참고문헌 (Reference)

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