检索结果-南通市图书馆

Bale Density and Moisture Content Effects on the Losses of Baled Alfalfa

Journal of Agricultural Science and Technology(A) 2012年第5期2卷 667-672页

作者： Sadegh Afzalinia aminallah masoumi Abdolhamid Karimi Dadgar Mohammadi Department of Agricultural Engineering Research Fars Research Center for Agriculture and Natural Resources Shiraz P.O. Box71555-617 lran Department of Agricultural Engineering Isfahan University of Technology Isfahan P.O. Box 84154 lran Fars Research Center for Agriculture and Natural Resources Shiraz P.O. Box 71555-617 lran

In order to reduce alfalfa losses, the effect of bale density and alfalfa moisture content on the losses of baled alfalfa during the baling and transportation process was determined in this study. Three ranges of moisture content including 14%-17%, 17% -20%, and 20%-23% （wb） were considered in this study. Bale densities considered in this research were 110-120, 120-130, 130-140, and 140-150 kg/m3. The study was conducted in the form of a split-plot experimental design with three replications and a small rectangular baler was used to bale the second cut alfalfa. Alfalfa losses were measured in the pickup system and compression chamber of baler and losses were separated to stems and leaves. Alfalfa losses were also determined during the bale transportation process. Results showed that alfalfa moisture content had significant effect on the leaf and stem losses of the baler pickup system and alfalfa losses during the transportation process while; leaf and stem losses of baler compression chamber were not affected by alfalfa moisture content. Results also revealed that the bale density had no significant effect on the leaf and stem losses of the baler pickup system and alfalfa losses during the transportation process but leaf and stem losses of baler compression chamber were significantly affected by the bale density.

关键词： Alfalfa bale density alfalfa moisture content alfalfa losses.

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

Effect of Coriolis and centrifugal forces on flow and heat transfer at high rotation number and high density ratio in non orthogonally internal cooling channel

引用

Chinese Journal of Aeronautics 2017年第1期30卷 216-234页

作者： Brahim Berrabah Miloud aminallah Department of Mechanical Engineering Materials and Reactive Systems Laboratory Faculty of Technology Djillali Liabes University Sidi Bel-Abbes 22000 Algeria

Numerical predictions of three-dimensional flow and heat transfer are performed for a two-pass square channel with 45° staggered ribs in non-orthogonally mode-rotation using the second moment closure model. At Reynolds number of 25,000, the rotation numbers studied were 0,0.24, 0.35 and 1.00. The density ratios were 0.13, 0.23 and 0.50. The results show that at high buoyancy parameter and high rotation number with a low density ratio, the flow in the first passage is governed by the secondary flow induced by the rotation whereas the secondary flow induced by the skewed ribs was almost distorted. As a result the heat transfer rate is enhanced on both co-trailing and co-leading sides compared to low and medium rotation number. In contrast, for the second passage, the rotation slightly reduces the heat transfer rate on co-leading side at high rotation number with a low density ratio and degrades it significantly on both co-trailing and co-leading sides at high buoyancy parameter compared to the stationary, low and medium rotation numbers. The numerical results are in fair agreement with available experimental data in the bend region and the second passage, while in the first passage were overestimated at low and medium rotation numbers.

关键词： Blade cooling Computational FluidDynamic (CFD) Heat transfer High buoyancy parameter High rotation number

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

Heat Transfer Enhancement in a Parabolic Trough Solar Receiver using Longitudinal Fins and Nanofluids

引用

Journal of Thermal Science 2016年第5期25卷 410-417页

作者： Amina Benabderrahmane Miloud aminallah Samir Laouedj Abdelylah Benazza J.P.Solano Laboratory of Reactive Systems and Materials DjiUali Liabes UniversitySidi Bel AbbesAlgeria Ingenieria Termica y de Fluidos Univcrsidad Politecnica de CartagenaCartagenaSpain

In this paper,we present a three dimensional numerical investigation of heat transfer in a parabolic trough collector receiver with longitudinal fins using different kinds of nanofluid,with an operational temperature of 573 K and nanoparticle concentration of 1% in *** outer surface of the absorber receives a non-uniform heat flux,which is obtained by using the Monte Carlo ray tracing *** numerical results are contrasted with empirical results available in the open literature.A significant improvement of heat transfer is derived when the Reynolds number varies in the range 2.57×104≤ Re≤ 2.57×105,the tube-side Nusselt number increases from 1.3 to 1.8 times,also the metallic nanoparticles improve heat transfer greatly than other nanoparticles,combining both mechanisms provides better heat transfer and higher thermo-hydraulic performance.

关键词： numerical study Monte Carlo ray trace parabolic trough collector heat transfer longitudinal fins nanofluid

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

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

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：