Development of High-Performance Heat Transport Device Using Magnetic Fluid and Intermittent Magnetic Field

利用磁流体和间歇磁场开发高性能传热装置

基本信息

批准号：
16560183
负责人：
KITAMURA Kenzo
金额：
$ 1.98万
依托单位：
TOYOHASHI UNIVERSITY OF TECHNOLOGY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2005
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16560183/
关键词：
Heat Transfer Heat Transfer Enhancement Magnetic Field Intermittent Magnetic Field Spike Pattern 熱伝導熱伝導率

项目摘要

A unique technique for the heat transfer enhancement that utilizes the interaction of a magnetic fluid and an intermittent magnetic field was proposed in the present study. It is known that the magnetic fluid shows spiky interface when the magnetic filed is imposed. The spiky interface and a flat interface will be generated alternately by putting on and off the magnetic field, and this will cause a bulk fluid motion of magnetic fluid, and thus, will result in the marked enhancement of the heat transfer. The rate of the heat transfer enhancement by the above method was investigated quantitatively in the present study. For the sake of this, the magnetic fluid was placed in a shallow container. The container was consisted with heated bottom wall and cooled top wall and air layer existed over the magnetic field. The heat transfer rates between the hot to cold walls were measured by varying the strength and frequencies of imposed magnetic field systematically. The results showed that the heat transfer rates under the intermittent magnetic field are increased by 3 to 6 times larger than those without magnetic field. In particular, the highest enhancement ratio was obtained when the water was replaced with air layer over the magnetic fluid. The optimum strength and the frequencies of the magnetic filed, the depth of the magnetic fluid on heat transfer were also discussed. The present technique will be utilized for the cooling of electronic equipment.

在本研究中，提出了一种利用磁性流体和间歇性磁场相互作用的传热增强的独特技术。众所周知，当施加磁性磁性时，磁性流体显示出尖峰界面。尖峰界面和平面界面将通过磁场上和关闭磁场交替生成，这将导致磁性流体的大量流体运动，因此会导致热传递的明显增强。在本研究中对上述方法的传热增强速率进行了数量研究。为此，将磁液放在浅容器中。容器由加热的底壁和冷却的顶壁组成，并且在磁场上存在空气层。通过系统地改变强度磁场的强度和频率来测量热壁之间的传热速率。结果表明，间歇性磁场下的传热速率比没有磁场的传热率增加了3至6倍。特别是，当水层在磁性流体上取代水时，获得了最高的增强比。还讨论了最佳强度和磁性磁性的频率，磁性流体在传热时的深度进行了讨论。目前的技术将用于冷却电子设备。