完整后设资料纪录
DC 栏位 | 值 | 语言 |
---|---|---|
dc.contributor.author | 钟浩荣 | en_US |
dc.contributor.author | Chung, Hau-Rong | en_US |
dc.contributor.author | 杨锦钏 | en_US |
dc.contributor.author | 谢德勇 | en_US |
dc.contributor.author | Yang, Jinn-Chuang | en_US |
dc.contributor.author | Hsieh, Te-Yung | en_US |
dc.date.accessioned | 2014-12-12T01:24:58Z | - |
dc.date.available | 2014-12-12T01:24:58Z | - |
dc.date.issued | 2011 | en_US |
dc.identifier.uri | http://140.113.39.130/cdrfb3/record/nctu/#GT079516807 | en_US |
dc.identifier.uri | http://hdl.handle.net/11536/41142 | - |
dc.description.abstract | 为能探讨高含砂水流运移现象并提供实际规划应用参考,本研究采水平正交曲线、垂向sigma座标系统之静水压浅水波方程式,发展一三维高含砂水流沉滓运移数值模式。控制方程式以水平垂直分离概念,分为水深平均二维方程式与流速差异量方程式,搭配三维连续方程式求解三维流场。沉滓运移控制方程式分为三维质量传输方程式、作用层连续方程式与底床连续方程式。高含砂效应考量二次式流变关系反应非牛顿流体特性,以状态函数反应含砂浓度对密度之影响,并采用考虑高含砂效应之悬浮载与底床载经验式,反应高含砂水流沉滓运移与浓度变化。 高含砂水流及沉滓运移模式应用上需率定之相关参数甚多,因此首先进行模式参数敏感度分析,探讨影响水理、浓度与底床冲淤模拟结果重要参数之权重。另研选数组高含砂水流实验案例进行模式测试,探讨水理及沉滓运移特性。探讨重点包含:流变关系之阻力使溃坝涌波移动一段距离后发生停止运移之现象;弯道水位超高变化受流变关系之影响;流变关系与密度对底床载运移量之影响;并厘清落淤速度与剪力速度之比值,可判断两种紊流扩散系数分布于模拟三维悬浮载浓度分布之适用性。最后以实际应用角度,建立高含砂水流效应下,定床水深、流速与底床剪力相对于清水流之增量及以动床观点探讨底床载对底床冲淤之影响,以简易关系式之型式供工程规划设计应用之参考。 | zh_TW |
dc.description.abstract | To investigate the transport behavior of hyper-concentrated flow and as a result to provide as a reference for engineering planning of practical cases, a hydrostatic three-dimensional model for hyper-concentrated flow and sediment transport in alluvial channels was developed in this study. By following the vertical and horizontal splitting concept (VHS), the shallow water flow governing equations were split into two parts including the depth-averaged two-dimensional equations and velocity defect equation in vertical direction. The former one was transformed into orthogonal curvilinear coordinate system; the latter one was derived as the form of sigma coordinate. Incorporated with continuity equation, the three-dimensional velocity field can therefore be solved. Sediment transport governing equations include three-dimensional mass transport equation, active-layer continuity equation, and bed-layer continuity equation. The effects of hyper-concentrated flow were treated as follows: a quadratic rheological relation was used to reflect the characteristics of non-Newtonian fluid; a state function was used to reflect the influence of concentration to density; the empirical suspended- and bed-load formulae with hyper-concentrated flow effect were used for the sediment transport computation. Sensitivity analysis was performed first to identify the weighting of parameters to be calibrated in the model. The influence extent induced by the parameters on water flow, suspended sediment concentration, and bed evolution, thereafter were examined and justified. To further investigate the characteristics of hyper-concentrated flow and sediment transport, several sets of experimental cases collected from the literatures were simulated. The case of dam-break wave propagation of non-Newtonian fluid was simulated to demonstrate the limit of traveling distance of hyper-concentrated flow. A channel bend flow experiment with 40% volume concentration of sediment was studied to investigate the effect of hyper-concentrated flow on super-elevation of water surface. A criterion of ratio of falling velocity and shear velocity was numerically examined and justified based on experimental data as a baseline for choosing the proper distribution type of turbulent diffusivity for simulation of suspended-load movement. At last, simple and concise regression relations for the increments of water depth, velocity, bed shear stress, and bed change caused by the hyper-concentrated flow were established for application of engineering planning and design. | en_US |
dc.language.iso | zh_TW | en_US |
dc.subject | 高含砂水流 | zh_TW |
dc.subject | 三维模式 | zh_TW |
dc.subject | 流变关系 | zh_TW |
dc.subject | 沉滓运移 | zh_TW |
dc.subject | 悬浮载 | zh_TW |
dc.subject | 底床载 | zh_TW |
dc.subject | hyper-concentrated flow | en_US |
dc.subject | three-dimensional model | en_US |
dc.subject | rheological relation | en_US |
dc.subject | sediment transportation | en_US |
dc.subject | suspended load | en_US |
dc.subject | bed load | en_US |
dc.title | 河道三维高含砂水流沉滓运移模式发展与应用 | zh_TW |
dc.title | Development and Application of a Three-Dimensional Model for Hyper-Concentrated Flow and Sediment Transport in Alluvial Channels | en_US |
dc.type | Thesis | en_US |
dc.contributor.department | 土木工程学系 | zh_TW |
显示于类别: | Thesis |
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