Study on the permanent-magnetically-driven flow of magnetic nanofluids in a microtube

• Main Authors: Wen-Yu Zhang, 張文昱
• Other Authors: Huei-Chu Weng
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/40501814241661060159

碩士 === 中原大學 === 機械工程研究所 === 104 === This study conducts a research of permanent-magnetically-driven flow of magnetic nanofluids in a microtube. The main purpose is to investigate the influence of volume fraction of particles, magnetic field gradient, and magnetic disk rotational speed on the magnetic driving force in the microtube. First, water-based magnetite (Fe3O4) nanofluids are prepared, and experimental measurements of their material properties are made. Further, the theoretical formula of magnetic driving force is provided, and some experiments are done to verify the validation of the formula. Finally, the analysis of the characteristics of the permanent-magnetically-driven flow of magnetic nanofluids in a microtube is conducted through experimental data of the volume flow rate and calculations of the magnetic driving formula. Experimental results are found that the magnetic driving force increases with the increase in the particle volume fraction, magnetic field gradients, and magnetic-disk rotational speed. At higher values of these parameters, the increasing becomes slowly. Moreover, the magnetic driving force increases dramatically with the decrease in the distance between the magnetic disk and the microtube. All magnetic effects could be magnified in a larger microtube.