检索结果-南通市图书馆

Estimating the impact of azimuth-angle variations on photovoltaic annual energy production

Clean Energy 2019年第1期3卷 47-58页

作者： Mahmoud Dhimish Santiago Silvestre Laboratory of Photovoltaics University of HuddersfieldQueensgateHD13DHHuddersfieldUK MNT Group Electronic Engineering DepartmentUniversitat Politecnica de Catalunya(UPC)BarcelonaTechC/Jordi Girona 1-3Campus Nord UPC08034 BarcelonaSpain

The performance of a photovoltaic(PV)installation is affected by its tilt and azimuth angles,because these parameters change the amount of solar energy absorbed by the surface of the PV modules.Therefore,this paper demonstrates the impact of the azimuth angle on the energy production of PV installations.Two different PV sites were studied,where the first comprises PV systems installed at-13°,-4°,+12°and+21°azimuth angles in different geographical locations,whereas the second PV site included adjacent PV systems installed at-87°,-32°,+2°and+17°azimuth angles.All the investigated PV sites were located in Huddersfield,UK.In summary,the results indicate that PV systems installed between-4°and+2°presented the maximum energy production over the last 4 years,while the worst energy generation were observed for the PV system installed at an azimuth angle of-87°.Finally,the probability projections for all observed azimuth angles datasets have been assessed.Since PV systems are affected by various environmental conditions such as fluctuations in the wind,humidity,solar irradiance and ambient temperature,ultimately,these factors would affect the annual energy generation of the PV installations.For that reason,we have analysed the disparities and the probability of the annual energy production for multiple PV systems installed at different azimuth angles ranging from-90°to+90°degrees,and affected by different environmental conditions.These analyses are based on the cumulative density function modelling technique as well as the normal distribution function.

关键词： photovoltaics azimuth angle energy production CDF modelling

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 investigation on free air blast loads generated from center-initiated cylindrical charges with varied aspect ratio in arbitrary orientation

引用

Defence Technology（防务技术） 2022年第9期18卷 1662-1678页

作者： Chu Gao Xiang-zhen Kong Qin Fang Jian Hong Yin Wang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLAJiangsuNanjing210007China Inner Mongolia University of Finance and Economics Inner MongoliaHohhot010070China Engineering Research Center for Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityJiangsuNanjing211189China

In current guidelines, the free air blast loads(overpressure and impulse) are determined by spherical charges, although most of ordnance devices are more nearly cylindrical than spherical in geometry. This may result in a great underestimation of blast loads in the near field and lead to an unsafe design.However, there is still a lack of systematic quantitative analysis of the blast loads generated from cylindrical charges. In this study, a numerical model is developed by using the hydrocode AUTODYN to investigate the influences of aspect ratio and orientation on the free air blast loads generated from center-initiated cylindrical charges. This is done by examining the pressure contours, the peak overpressures and impulses for various aspect ratios ranged from 1 to 8 and arbitrary orientation monitored along every azimuth angle with an interval of 5°. To characterize the distribution patterns of blast loads,three regions, i.e., the axial region, the vertex region and the radial region are identified, and the propagation of blast waves in each region is analyzed in detail. The complexity of blast loads of cylindrical charges is found to result from the bridge wave and its interaction with primary waves. Several empirical formulas are presented based on curve-fitting the numerical data, including the orientation where the maximum peak overpressure emerges, the critical scaled distance beyond which the charge shape effect could be neglected and blast loads with varied aspect ratio in arbitrary orientation, all of which are useful for blast-resistant design.

关键词： Cylindrical charge Blast loads Aspect ratio azimuth angle Bridge wave

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

High Precision Biaxial Solar Tracker

High Precision Biaxial Solar Tracker

引用

International Conference on Industrial Technology and Management Science(ITMS 2015)

作者： Z.Y.XIA X.Y.CHEN S.G.CHEN L.H.HU D.S.WU G.J.JIN Mechanical and Electronical Engineering College Fujian Agriculture and Forestry University

In this paper, a high precision biaxial solar tracker is designed, which is an application platform, can be used in solar photovoltaic projects and solar heat projects. Based on astronomy algorithm, we write a program in a Delta PLC to get the position of the sun by calculating its azimuth angle and altitude angle. Two DC motors is controlled by PLC to drive the solar tracker to rotate around both azimuth axis and altitude axis. Besides, three additional functions: hibernation, typhoon defender and snow cleaning, are designed to improve validity and reliability of the solar tracker. With Pro/E and ANSYS Workbench software, strength analysis in typhoon weather is made to assure the reliability of the solar tracker.

关键词： high precision solar tracker astronomy algorithm azimuth angle altitude angle

来源： cnki会议评论

在线全文

cnki会议

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：