Investigation on the Motion, Diffusion and Deposition of Direct Dumped Soil in Flowing Waters

直接倾倒土体在流水中的运动、扩散和沉积研究

• 批准号: 08455232
• 负责人: AKIYAMA Juichiro
• 金额: $ 4.8万
• 依托单位: Kyushu Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08455232/
• 关键词: Density Current; Turbulent Thermal; Gravity Current; Solid-Liquid Two Phase Flow; LES; Reclamation; Turbidity Diffusion; サーマルモデル; サーマル; 海洋汚濁

It is found, from theoretical as well as experimental studies, that the maximun half width H, average buoyancy forceB and falling velocity V of both saline and particle clouds falling in quiescent waters have the following relationships ; against falling distance z H = KィイD21ィエD2z, V = KィイD22ィエD2zィイD1-1/2ィエD1 B = KィイD23ィエD2zィイD1-2ィエD1 initial total buoyancy WィイD20ィエD2 H = CィイD21ィエD2, B = CィイD22ィエD2WィイD20ィエD2, and V = CィイD23ィエD2WィイD31/2(/)0ィエD3. KィイD21ィエD2 for H, B and V in saline clouds become constant although their values are different. On the other hand, KィイD21ィエD2 in particle cloud clouds are function of particle Reynolds number Rp and their dependence on Rp are different for H, B and V. Similar relationships are also true for CィイD21ィエD2. Both saline and particle clouds falling in flowing waters also follows the same relationships against z and WィイD20ィエD2 as the case of quiescent waters although the buoyant clouds advect at the speed of ambient water flow velocity U. But ambient wa … More ter flow alters the values of KィイD21ィエD2. The functional relationships for KィイD21ィエD2 expressed in terms of Rp and U are reduced from extensive experimental study.It is found experimental that major flow characteristics of both saline and particle clouds before and after impingement on the bottom boundary are not dependent on both initial total buoyancy force WィイD20ィエD2 and ambient water depth h.Major flow characteristics of buoyant clouds traveling along bottom boundary after impingement can be distinguished into two regions ; transitional and gravity-current-like regions. Based on careful experimental work, we developed the functional relationships, that are able to adequately describe major flow characteristics of buoyant clouds in each region.A new numerical simulation model for high concentration turbidity clouds is developed, utilizing Large Eddy Simulation (LES) and one-fluid model, coupled with a newly developed CCS scheme for advective-diffusion equation as well as the modified Smagorinsky model for SGS model. Model constants are determined by comparing with experimental results in the falling stage. Using the model constants, it is demonstrated that the proposed numerical model can well simulate both the motion of particle clouds and depositional profile of particles. Capability of the model is demonstrated further through numerical simulations in the presence of a silt fence. Less

本文从理论和实验两方面研究发现，盐云和粒子云在静止沃茨中的最大半宽H、平均浮力B和下落速度V之间有下列关系：相对于下落距离z H = K D21 D2 z，V = K D22 D2 z D1-1 - 2 D1 B = K D23 D2 z D1-2 D1初始总浮力W D20 D2 H = C D21 D2，B = C轴D22轴D2 W轴D20轴D2，V = C轴D23轴D2 W轴D31/2（/）0轴D3。盐云中H、B和V的K_（max）D_（21）K_（max）D_（22）虽然数值不同，但都趋于恒定。另一方面，粒子云中的K_（10）D_（21）D_（22）是粒子雷诺数R_p的函数，它们对R_p的依赖性对于H、B和V是不同的。对于C_（10）D_（21）D_（21）D_（22）也是类似的关系。落在流动沃茨中的盐云和粒子云也遵循与静止沃茨的情况相同的关于z和W的关系，尽管浮力云以环境水流速度U的速度平流。但是环境温度 ...更多信息 水流改变了K_（max）D_（21）K_（max）D_（22）的值。本文通过大量的实验研究，导出了K_p_D ~（21）K_p_D ~（21）K_p_D ~（22）与R_p和U的函数关系式。实验发现，盐云和颗粒云撞击底边界前后的主要流动特性与初始总浮力W_p_D ~（20）K_p_D ~（22）和环境水深h无关。浮云沿沿着底边界运动的主要流动特性撞击后的流体可分为两个区域：过渡区和类重力流区。在实验研究的基础上，建立了能较好地描述各区域主要流动特征的函数关系式，并采用大涡模拟（LES）和单流体模式，结合对流扩散方程的CCS格式和SGS模式的Smagorinsky修正模式，建立了一个新的高浓度混浊云数值模拟模式。通过与实验结果的比较，确定了下降阶段的模型常数。结果表明，该数值模型能较好地模拟颗粒云的运动和颗粒的沉积轮廓。该模型的能力进一步证明了通过数值模拟中存在的淤泥栅栏。少

项目成果

X.Ying,J.Akiyama,M.Ura: "Large Eddy Simulation of Heavy Turbulent Thermal"Annual Journal of Hydraulic Engineering. Vol.43. 899-904 (1999)

X.Ying，J.Akiyama，M.Ura：“强湍流热力的大涡模拟”水利工程学报。

X.Ying,J.Akiyama et al.: "The Large Eddy Simulation of Heavy Turbulent Thermal" Annual Journal of Hydraulic Engineering. Vol.43. 899-904 (1999)

X.Ying，J.Akiyama等：“强湍流热力的大涡模拟”水利工程学报。

秋山壽一郎ら: "静水中に瞬間的に投下された重たい流体塊の流動特性に関する研究"水工学会論文集. 第42巻. 529-534 (1998)

Juichiro Akiyama 等人：“重流体瞬间落入静止水中的流动特性的研究”，日本水利学会学报，第 42 卷，529-534（1998 年）。

秋山壽一郎ら: "静水中に瞬間的に投下された重い流体塊の底面衝突後の挙動"水工学会論文集. 第43巻. 1115-1120 (1999)

Juichiro Akiyama 等人：“底部碰撞后重液团瞬间落入静止水中的行为”，日本水利工程师学会汇刊，第 43 卷，1115-1120（1999 年）。

J.Akiyama et al.: "Swarms of Fine Particles Falling Through Quiescent and Flowing Waters"J.of Hydroscience and Hydraulic Engeineering. Vol.18(掲載予定). (2000)

J. Akiyama 等人：“穿过静止和流动水域的细小粒子群”，水科学与水利工程杂志，第 18 卷（即将出版）。