External forced convection from circular cylinders with surface protrusions
External forced convection from circular cylinders with surface protrusions
复制标题
具有表面突起的圆柱体的外部强制对流
DOI：
10.1016/j.ijheatmasstransfer.2016.03.092
复制
发表时间：
2016-08
影响因子：
5.2
通讯作者：
Dong Zhenying
中科院分区：
文献类型：
--
作者：
Li Saiwei;Zhou Tian;Sun Zhiqiang;Dong Zhenying
表面结构在换热设备中的应用有助于提高换热设备的换热性能。在本研究中，添加了表面突起作为对横流中圆柱体的修改。改装后的圆柱体保持恒温，并加热流过它的冷空气。首先考察了改进型圆柱体的突起数、无因次突起高度和两种对准方式对换热性能的影响。对于不超过6个凸起的改进圆柱体，我们观察到时间和空间平均Nusselt数的增加。然后对改进后的圆柱体表面的局部努塞尔数以及温度场和流场进行了考察，发现凸起之间的缺口对局部换热造成了较大的恶化。在此基础上，提出了两种不同的初始凸起设计方案，以进一步提高换热性能。第一种方案是在圆柱体表面对称地施加一对突起，在这种情况下，我们研究了突起高度、突起宽度和两系列突起放置的影响。第二种选择是逐渐填充突起之间的凹槽，在这种情况下，我们研究了突起高度、充填程度和两种对齐方式的影响。与圆柱体相比，双凸起设计和缺口填充设计在时间和空间平均努塞尔数上分别提高了7%和2%，同时分别伴随着8%和16%的阻力损失。
The application of surface structures to heat exchanging devices can help to enhance their heat transfer performance. In this study, surface protrusions were added as a modification to the circular cylinder in crossflow. The modified cylinder maintained a constant temperature and heated the cool air that flowed over it. We first investigated the influence on the heat transfer performance of the number of protrusions, the non-dimensional protrusion height, and two alignment modes of the modified cylinders. For the modified cylinders with no more than six protrusions, we observed increase in the temporally and spatially averaged Nusselt number. Then, we inspected the local Nusselt number along the modified cylinder surface as well as the temperature and flow fields, and found that the notches between the protrusions caused major deterioration to local heat transfer. Based on the observation, two alternative configurations to the initial protrusion design were proposed to further enhance the heat transfer performance. The first alternative was to apply a pair of protrusions symmetrically on the cylinder surface, in which case we studied the effects of the protrusion height, protrusion width, and two series of protrusion placements. The second alternative was to gradually fill the notches between the protrusions, in which case we studied the effects of the protrusion height, degree of filling, and two modes of alignment. Compared to the circular cylinder, the dual protrusion design and the notch-filling design achieved as much as 7% and 2% increase in the temporally and spatially averaged Nusselt number, while being accompanied by 8% and 16% drag penalty, respectively.
登录
查看更多内容
在 Re-D=5.4 x 10(4) 时测量仙人掌模拟沟槽圆柱体周围的流动：壁压波动和流动模式
影响因子：
3.6
作者：
Wang Shao Fei;Liu Ying Zheng;Zhang Qing Shan
通讯作者：
Zhang Qing Shan
影响因子：
2.4
作者：
Adnan M. El-Makdah;G. F. Oweis
通讯作者：
Adnan M. El-Makdah;G. F. Oweis
DOI：
10.1016/j.ijheatmasstransfer.2014.09.077
发表时间：
2015-02
影响因子：
5.2
作者：
S. Lorente;A. Bejan;J. Niu
通讯作者：
S. Lorente;A. Bejan;J. Niu
DOI：
10.1016/j.ijheatmasstransfer.2007.09.013
发表时间：
2008-06-01
影响因子：
5.2
作者：
Elyyan, Mohammad A.;Rozati, Ali;Tafti, Danesh K.
通讯作者：
Tafti, Danesh K.
DOI：
10.1016/j.ijheatmasstransfer.2013.04.055
发表时间：
2013-09
影响因子：
5.2
作者：
Jonghyeok Lee;Kwan-Soo Lee
通讯作者：
Jonghyeok Lee;Kwan-Soo Lee