全文获取类型
收费全文 | 89篇 |
免费 | 14篇 |
国内免费 | 4篇 |
专业分类
化学 | 5篇 |
力学 | 32篇 |
综合类 | 1篇 |
数学 | 8篇 |
物理学 | 61篇 |
出版年
2022年 | 7篇 |
2021年 | 4篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 1篇 |
2013年 | 10篇 |
2012年 | 10篇 |
2011年 | 9篇 |
2010年 | 5篇 |
2009年 | 7篇 |
2008年 | 3篇 |
2007年 | 7篇 |
2006年 | 5篇 |
2005年 | 2篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2002年 | 2篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
排序方式: 共有107条查询结果,搜索用时 15 毫秒
91.
General exact solution of the fin problem with the power law temperature‐dependent thermal conductivity
下载免费PDF全文
![点击此处可从《Mathematical Methods in the Applied Sciences》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Abass H. Abdel Kader Mohamed S. Abdel Latif Hamed M. Nour 《Mathematical Methods in the Applied Sciences》2016,39(6):1513-1521
In this paper, the general exact implicit solution of the second‐order nonlinear ordinary differential equation governing heat transfer in rectangular fin is obtained using Lie point symmetry method. General relationship among the fin efficiency, the rate of heat transfer from the entire fin, the fin effectiveness, and the thermo‐geometric fin parameter is obtained for any value of the mode of heat transfer n and the constant β. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
92.
为研究变角度百叶窗结构对平行流蒸发器换热性能的影响,文中建立了一种均匀角度百叶窗和两种变角度百叶窗的计算模型;采用fluent软件数值模拟了空气侧的传热和流动过程,得到了百叶窗翅片的速度场、温度场及压力场;将数值模拟结果与相关文献实验关联式结果进行对比,验证了数值模拟的可行性,分析了迎面风速对换热和压降特性的影响;并利用公式j/f1/3,比较了三种翅片的综合性能,发现变角度百叶窗翅片综合性能优于均匀角度百叶窗翅片。 相似文献
93.
The entransy theory developed in recent years is used to optimize the aspect ratio of a plate fin in heat convection.Based on a two-dimensional model,the theoretical analysis shows that the minimum thermal resistance defined with the concept of entransy dissipation corresponds to the maximum heat transfer rate when the temperature of the heating surface is fixed.On the other hand,when the heat flux of the heating surface is fixed,the minimum thermal resistance corresponds to the minimum average temperature of the heating surface.The entropy optimization is also given for the heat transfer processes.It is observed that the minimum entropy generation,the minimum entropy generation number,and the minimum revised entropy generation number do not always correspond to the best heat transfer performance.In addition,the influence factors on the optimized aspect ratio of the plate fin are also discussed.The optimized ratio decreases with the enhancement of heat convection,while it increases with fin thermal conductivity increasing. 相似文献
94.
95.
96.
带间断性矩肋的平行平板通道中三维流动与换热的数值模拟 总被引:1,自引:0,他引:1
1数学描述与计算方法周期性变化的几何结构是广泛应用的一种强化换热形式*‘]。文献中有关的数值研究多限于二维清形,三维的研究相对较少。本文针对沿流向周期性布置矩肋的平行平板通道,对层流周期性充分发展的流动与换热进行了三维数值模拟。计算单元如图1所示。对于不可压缩流体,忽略体积力时的控制方程为:图1矩助通道计算单元表1式(l)中各乡变量的含义式中d取不同值的对应关系见表1。设通道几何周期长度为S,则对充分发展状态的计算单元进出边界有如下关系:据文献*,周期性充分发展流动的压力可以分解为两部分:式中o为一个周… 相似文献
97.
In this article, studies are made on frost formation and flow over a fin and tube heat exchanger due to natural convection for various conditions of relative humidity, air ambient temperature, and mean refrigerant temperature. The results include frost deposition, steps of frost formation, and its effect on heat transfer rate for different conditions. The results show that frost is formed only on the tip of the fins with higher thickness from top to bottom due to small distance between the fins. Frost causes to trap the air which increases the thermal resistance and reduces heat transfer in the system. 相似文献
98.
The Green’s function method is applied for the transient temperature of an annular fin when a phase change material (PCM) solidifies on it. The solidification of the PCMs takes place in a cylindrical shell storage. The thickness of the solid PCM on the fin varies with time and is obtained by the Megerlin method. The models are found with the Bessel equation to form an analytical solution. Three different kinds of boundary conditions are investigated. The comparison between analytical and numerical solutions is given. The results demonstrate that the significant accuracy is obtained for the temperature distribution for the fin in all cases. 相似文献
99.
近空间飞行器的气动复合控制原理及研究进展 总被引:1,自引:0,他引:1
简单回顾与讨论了在飞行器穿越大气层时,使用气动复合控制方案的必要性与可能性.其中最复杂情况为发动机喷流推力与舵面空气动力共同使用所形成的复合控制.喷流与外流相撞引起的强干扰形成了十分复杂的干扰流场,文中介绍了复杂流动形成的原因、流场结构的特点以及干扰引起的流场改变影响了飞行器性能的预估.基于3种研究途径:理论建模与数值模拟技术、地面试验模拟技术、飞行试验技术的研究,以及它们的发展及互相验证, 用来预估飞行器的性能.为了保证地面模拟与真实飞行之间存在相似关系, 研究相似准则的作用,及分析目前的模拟能力, 涉及到许多空气动力学界至今尚未解决的难题,为了解决这些困难对今后的研究及应用提出了多方面的需求. 相似文献
100.
A novel non rectangular structure of Fin field-effect transistor with the modified channel is introduced as the solution of corner effects. In the proposed FinFET, the top region of fin has cylindrical structure and the bottom region of the fin has a rounded shape. The extended bottom region of fin with a round shape reduces the self-heating effects by distributing the heat from the widespread edges. The top cylindrical region of fin adjusts the corner effects and improves the gate controllability over the channel. The proposed structure with the modified channel which is called MC-FinFET is proven to have better thermal stability, lower hot carrier and self heating effects, improved short channel effects, reduced DIBL and better subthreshold characteristics in comparison with a conventional FinFET. Here, by a thermal conductivity model the effect of fin shape on the thermal resistance and the effective width of the proposed irregular FinFET is analyzed. Moreover, the thermal sensitivity of electro-thermal characteristics in the proposed structure is evaluated with three-dimensional simulations. The superiority of the MC-FinFET is owing to the sharp edges elimination for reducing the self-heating and corner effects. The electro-thermal results demonstrate the ability of MC-FinFET as a higher performance device over the conventional one. 相似文献