检索结果-南通市图书馆

Numerical and experimental studies of flow field in hydrocyclone with air core

Transactions of Nonferrous Metals Society of China 2014年第8期24卷 2642-2649页

作者：崔宝玉魏德洲高淑玲刘文刚 Yu-qing FENG 东北大学资源与土木工程学院沈阳110819 CSIRO Computational Informatics

For the flow field in a d50 mm hydrocyclone, numerical studies based on computational fluid dynamics (CFD) simulation and experimental studies based on particle image velocimetry (PIV) measurement were carried out respectively. The results of two methods show that air core generally forms after 0.7 s, the similar characteristics of air core can be observed. Vortexes and axial velocity distributions obtained by numerical and experimental methods are also in good agreement. Studies of different parameters based on CFD simulation show that tangential velocity distribution inside the hydrocyclone can be regarded as a combined vortex. Axial and tangential velocities increase as the feed rate increases. The enlargement of cone angle and overflow outlet diameter can speed up the overflow discharge rate. The change of underflow outlet diameter has no significant effect on axial and tangential velocities.

关键词： hydrocyclone computational fluid dynamics particle image velocimetry flow field air core

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

Effect of air core on the shape and discharge of the outflow through a bottom outlet

引用

Theoretical & Applied Mechanics Letters 2013年第2期3卷 72-76页

作者： Yiyi Ma Yu Qian David Z. Zhu Department of Civil Engineering Zhejiang University Department of Civil and Environmental Engineering University of Alberta

Experiments were conducted to study the generation of air core and its effect on the outflow shape and discharge in a cylindrical water tank with a bottom well-designed outlet. Depending on the stages of the air core in the tank, the outflow shape can vary from a smooth water jet to a smooth spindle shape with air-core, and to water sprays. The diameter of the nozzle size also has influence on the outflow pattern. The existence of the penetrated air core can dramatically reduce the outflow discharge, with the discharge coefficient decreasing with the nozzle diameter.

关键词： air core discharge outflow shape spray vortex

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

air-core characteristics in a swirling tunnel flow

引用

Journal of Hydrodynamics 2022年第4期34卷 634-646页

作者： Jun-hu Nan Huan Gao Chao-qun Wang Kang-ning Ma James Yang Jia-fang Wei Guo-dong Li State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi'an University of TechnologyXi'an 710048China College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Civil and Architectural Engineering Royal Institute of Technology(KTH)StockholmSweden

A cost-effective technique to dissipate the energy in hydropower systems is the formation of a swirling flow within a *** such flows,an air core with a significant cross section usually *** reveal the air-core features in the horizontal tunnel of a high-head shaft spillway,laboratory tests,numerical modeling,and prototype observations are performed,to examine issues such as the formation of the air core,the interjacent air motion,the air-carrying capacity,and the scale *** is shown that the shape of the air core varies greatly in the axial and radial directions along the tunnel and that the center of the core deviates from the axis of the *** motion of the air within the core is caused by the combined action of the water entrainment on the inner surface of the swirling flow and the axial pressure difference in the air *** aeration process can be divided into five processes with respect to the changes of the gate openings.A theoretical expression is established for the air-carrying capacity of the swirling *** vacuum degree is the similarity condition of the air-carrying capacity of the swirling flow between the model and prototype tests based on the Froude law of the similitude,and this similarity condition is verified by both the model and prototype *** work provides a reference for the application of the swirling flows in horizontal hydropower tunnels.

关键词： Horizontal tunnel swirlingflow air core air-carrying capacity scale effect

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 analysis of vortex core phenomenon during draining from cylinder tank for various initial swirling speeds and various tank and drain port sizes

引用

Journal of Hydrodynamics 2013年第2期25卷 183-195页

作者： SOHN Chang Hyun SON Jong Hyeon PARK Il Seouk School of Mechanical Engineering Kyungpook National University

A dimple appears on a free surface while rotating a cylinder tank filled with liquid. The dimple starts to concentrically deeper to a drain port at the bottom center of the tank. Over time, the dimple penetrates the drain port, a free surface forms a long and slender string shape in the tank, and a so-called vortexing （air core） phenomenon occurs. The generation of a vortex core depends on the size of the tank and drain port, and on the properties of the liquid in the tank. In this study, the liquid level and the time at which the vortex core is initially generated are numerically investigated using different values of tank diameter, drain port diameter, and ini- tial tank rotational speeds. Instead of a full three-dimensional analysis, a two-dimensional axisymmetric simulation is conducted. The momentum conservation equation in the circumferential direction is additionally solved in the two-dimensional mesh system. Several non-dimensional variables are created： the ratio of the air core generation distance and tank diameter, the diameter ratio of the tank and drain port, the rotational Reynolds number, the rotational Froude number, and the rotational Weber number. Finally, the non-dimensional air core generation distance is correlated with the other non-dimensional parameters.

关键词： air core vortex core dip penetration vortexing draining

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

Effect of nozzle inlet parameters on the dry granulation atomization process of Si_(3)N_(4) ceramic bearing balls

引用

International Journal of Modeling, Simulation, and Scientific Computing 2021年第6期12卷 182-205页

作者： Dongling Yu Xiaohui Zhang Hongbin Luo Dahai Liao Nanxing Wu School of Mechanical and Electronic Engineering Jingdezhen Ceramic Institute Jingdezhen 333403 P.R.China

In this paper,the atomization characteristics of Si3N4 ceramic dry granulation affect the performance of Si3N4 ceramic bearing *** order to improve the dry granulation characteristics and the comprehensive performance of Si3N4 ceramic bearing balls,the atomization mechanism of the spinning nozzle used for Si3N4 dry granulation was studied in *** interaction between air and binder in the pressure-swirl nozzle is analyzed based on VOF method,the modified realizable k−εturbulence model is used to simulate the flow field inside and outside the pressure-swirl nozzle,the effects of nozzle inlet parameters including the number of tangential inlets and the deflection angle of tangential inlets on the binder volume fraction,velocity distribution and pressure distribution are *** results show that when the number of tangential inlets increases from 1 to 4,the swirl strength of gas–liquid two-phase in the nozzle increases,the mean diameter of air core increases from 1.51 mm to 2.01 mm,and the spray cone angle increases from 18.5◦to 26.4◦.Besides,when the deflection angle of tangential inlet increases from 0◦to 15◦,the swirl strength of gas–liquid two-phase in the nozzle with the deflection angle of tangential inlet of 10◦is the largest,and the mean diameter of air core and spray cone angle is 3.04 mm and 30.7◦,*** on the atomization experiment platform of the electric control fuel system,the mean diameter of air core and spray cone angle are measured,the micromorphology of Si3N4 particles is observed,which verifies the correctness of numerical *** the Si3N4 particles are prepared by dry granulation,taking the atomization performance of nozzle into consideration,the pressure-swirl nozzle with 4 tangential inlets and 10◦deflection angle should be selected.

关键词： Si_(3)N_(4)ceramic bearing balls pressure-swirl nozzle VOF method inlet parameters air core spray cone angle

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

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

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

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：