教師資料查詢 | 類別: 期刊論文 | 教師: 李政賢 CHENG-HSIEN LEE (瀏覽個人網頁)

標題:Multi-dimensional rheology-based two-phase model for sediment transport and applications to sheet flow and pipeline scour
學年104
學期2
出版(發表)日期2016/05/24
作品名稱Multi-dimensional rheology-based two-phase model for sediment transport and applications to sheet flow and pipeline scour
作品名稱(其他語言)
著者Lee, Cheng-Hsien; Low, Ying Min; Chiew, Yee-Meng
單位
出版者
著錄名稱、卷期、頁數Physics of Fluids 28(5), pp.053305(24 pages)
摘要Sediment transport is fundamentally a two-phase phenomenon involving fluid and sediments; however, many existing numerical models are one-phase approaches, which are unable to capture the complex fluid-particle and inter-particle interactions. In the last decade, two-phase models have gained traction; however, there are still many limitations in these models. For example, several existing two-phase models are confined to one-dimensional problems; in addition, the existing two-dimensional models simulate only the region outside the sand bed. This paper develops a new three-dimensional two-phase model for simulating sediment transport in the sheet flow condition, incorporating recently published rheological characteristics of sediments. The enduring-contact, inertial, and fluid viscosity effects are considered in determining sediment pressure and stresses, enabling the model to be applicable to a wide range of particle Reynolds number. A k − ε turbulence model is adopted to compute the Reynolds stresses. In addition, a novel numerical scheme is proposed, thus avoiding numerical instability caused by high sediment concentration and allowing the sediment dynamics to be computed both within and outside the sand bed. The present model is applied to two classical problems, namely, sheet flow and scour under a pipeline with favorable results. For sheet flow, the computed velocity is consistent with measured data reported in the literature. For pipeline scour, the computed scour rate beneath the pipeline agrees with previous experimental observations. However, the present model is unable to capture vortex shedding; consequently, the sediment deposition behind the pipeline is overestimated. Sensitivity analyses reveal that model parameters associated with turbulence have strong influence on the computed results.
關鍵字
語言英文(美國)
ISSN1089-7666
期刊性質國外
收錄於SCI;
產學合作
通訊作者
審稿制度
國別美國
公開徵稿
出版型式,電子版
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