检索结果-南通市图书馆

Lattice Boltzmann method for simulating flows in open-channel with partial emergent rigid vegetation cover

Journal of Hydrodynamics 2019年第4期31卷 717-724页

作者： Zhong-hua Yang Feng-peng Bai Wen-xin Huai Cheng-guang Li State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China Changjiang Water Resources Protection Institute Wuhan 430051 China Shandong Provincial Key Laboratory of Water Resources and Water Environment Water Resources Research Institute of Shandong Province Jinan 250013 China

Flows in open-channel with partial emergent rigid vegetation cover are simulated using the lattice Boltzmann method (LBM) described by the 2-D nonlinear shallow water equations. The effect of vegetation is represented with the vegetation roughness coefficient, which is related to the vegetation density, diameter of the vegetation elements and drag coefficient. The model is verified by three numerical tests: flow in a 180° curved open channel with partial vegetation cover at the outer bank, flow in a rectangular channel with a finite patch of vegetation and flow in a rectangular channel with a vegetated bank. Numerical results are compared with the experimental data, and the good agreement proved that the presented model can model the vegetated channel flows correctly.

关键词： open-channel flow rigid vegetation lattice Boltzmann method (LBM) shallow water equations vegetation roughness coefficient

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

TURBULENCE CHARACTERISTICS IN SMOOTH open-channel FLOW

引用

Science China Mathematics 1990年第2期33卷 244-256页

作者：董曾南丁元 Department of Hydraulic Engineering Tsinghua University

A flow in a smooth open channel can he divided into several regions along the flow direction, i. e. the laminar boundary layer, transition region, turbulent boundary layer, fully developed turbulent boundary layer and a uniform open-channel turbulent flow. The temporal mean and turbulent characteristics will not vary again in the course of the uniform open-channel flow. There is obviously a structure of different regions in the vertical direction of a smooth open-channel turbulent flow. The limits of different regions, the velocity profiles and characteristics of fluctuating velocities in such regions are given. When the aspect ratio W/H is larger than 10, the flow in the open channel may be considered as a 2-dimensional flow. The formulas of sectional averaged velocity and frictional loss factor are also given.

关键词： open-channel flow turbulence characteristics.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

宝存科技推出全球首款大量商用级别的高性能open-channel SSD

引用

世界电子元器件 2018年第8期 10-12页

在美国加州Santa Clara(圣克拉拉),上海宝存信息科技有限公司(Shannon Systems)携全新升级固态闪存产品亮相'Flash Memory Summit'。此次宝存科技推出全球首家大规模商用的基于NVME的openchannel SSD产品。宝存科技表示,本次发布的产品... 详细信息

在美国加州Santa Clara(圣克拉拉),上海宝存信息科技有限公司(Shannon Systems)携全新升级固态闪存产品亮相'Flash Memory Summit'。此次宝存科技推出全球首家大规模商用的基于NVME的openchannel SSD产品。宝存科技表示,本次发布的产品采用的原材料NAND颗粒,从3D MLC升级到目前最先进的3DTLC.

关键词： SSD open-channel SSD 闪存产品

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical simulation of turbulent flow in helically coiled open-channels with compound cross-sections

引用

Science China(Technological Sciences) 2004年第1期47卷 97-111页

作者： SHAO Xuejun WANG Hong CHEN Zhi Department of Hydraulic Engineering Tsinghua University Beijing 100084 China Department of Hydraulic Engineering Tsinghua University Beijing 100084 China Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

Turbulence structure in a helically coiled open channel flow is numerically simulated using three different turbulence models--the Launder and Ying model, the Naot and Rodi model, and the nonlinear k-ε Model (SY model). Simulation results were compared with observation of (i) turbulent flows in alternating point-bar type channel bends with rectangular sections, and (ii) straight open channel flows with compound cross-sections. Based on calculations of the impact of various channel curvatures on turbulence characteristics, accuracy of the three turbulence models was analyzed with observed data as a qualitative reference. It has been found out that the Launder and Ying model and the nonlinear k-ε Model are able to predict the same general trend as measured data, and the simulation of the effect of the centrifugal force on the formation of secondary currents produces a correct pattern.

关键词： curved open-channel turbulent flow, compound cross-section, orthogonal curvilinear coordinate system.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evaluating Two-Layer Models for Velocity Profiles in open-channels with Submerged Vegetation

引用

Journal of Geoscience and Environment Protection 2019年第1期7卷 68-80页

作者： Xiaonan Tang Department of Civil Engineering Xi’an Jiaotong-Liverpool University Suzhou China

For submerged vegetated flow, the velocity profile has two distinctive distributions in the vegetation layer in the lower region and the surface layer in the upper non-vegetated region. Based on a mixing-layer analogy, different analytical models have been proposed for the velocity profile in the two layers. This paper evaluates the four analytical models of Klopstra et al., Defina & Bixio, Yang et al. and Nepf against a wide range of independent experimental data available in the literature. To test the applicability and robust of the models, the author used the 19 datasets with various relative depths of submergence, different vegetation densities and bed slopes (1.8 × 10?6 - 4.0 × 10?3). This study shows that none of the models can predict the velocity profiles well for all datasets. The three models except Yang’s model performed reasonably well in certain cases, but Yang’s model failed in most the cases studied. It was also found that the Defina model is almost the same as the Klopstra model, if the same mixing length scale of eddies (λ) is used. Finally, close examination of the mixing length scale of eddies (λ) in the Defina model showed that when λ/h = 1/40(H/h)1/2, this model can predict velocity profiles well for all the datasets used.

关键词： Aquatic Vegetation Velocity Profile Vegetated Flow Analytical Model Rigid Vegetation open-channel Flow

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

ON THE DEVELOPMENT OF BOUNDARY LAYER FLOW OVER A GRAVEL-BED

引用

Chinese Science Bulletin 1991年第20期36卷 1725-1728页

作者：王晋军 Institute of Fluid Mechanics Beijing University of Aeronautics and Astronautics Beijing 100083 PRC

Ⅰ. INTRODUCTION It is well-known that when the flow enters the open-channel, the boundary layer was formed. Furthermore, with the development of boundary layer, a uniform open-channel flow was formed. In the case of uniform open-channel flow, the temporal mean and turbulent characteristics will not vary again. The distance between the inlet of the testing plate and

关键词： gravel-bed open-channel flow boundary layer.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：