靜電振動應用於離子風散熱之研究

Experimental studies on applying electrostatic vibration to ion wind cooling

藍朝誠(Chao-Coeng Lan)

指導教授 ： 王啟川

國立交通大學/工學院/機械工程系所/碩士(2015年)

https://doi.org/10.6842/NCTU.2015.00702

摘要

本研究提出一個新設計，用於改善自然對流的主動散熱設計，此設計無風扇馬達，透過高壓靜電產生的靜電吸附力，讓彈性金屬片產生類似壓電風扇的機械振動，同時運用其導電性質，將金屬片作為導電電極，使高壓電極及接地的鋁質散熱片中間形成空氣解離，產生複合式的振動離子風來增強散熱效率。實驗設計以7.5W功率加熱，測試不同電極間距、電極極性、電極材質、電極幾何形狀下的尖端位移、振動頻率及熱傳性能。實驗結果顯示，在電極間距25 mm，18 kV的工作電壓下，可產生尖端位移量8.62 mm，而在電極間距20 mm，18 kV工作電壓下，熱傳係數達38.85 W/m2K，約為自然對流的4.5倍。最後比較複合式散熱與純離子風散熱，根據實驗結果，在消耗功率0.13 W的情況下表現最好，複合式散熱的熱傳係數為32.03 W/m2K，相比離子風散熱的29.65 W/m2K增加了8.03%。

關鍵字

電液動力學 ； 離子風 ； 壓電風扇

並列摘要

This study presents a new design of electronic air-cooling using ionic electrostatic wind to improve natural convection cooling. The proposed electrostatic ion wind vibration cooling design features a hybrid effect which combines electrostatic vibration and ion wind. The wind by electrostatic vibration which can enhance the volumetric airflow with less power consumption. In the experiments, the maximum tip displacement is 8.6 mm for an electrode gap distance of 25 mm subject to an operating voltage of 18 kV. For a 7.5 W heat source, the maximum heat transfer coefficient is 38.85 W/m2K for an electrode gap distance of 20 mm at an operating voltage of 18 kV. The heat transfer enhancement reached 4.5 times relative to natural convection. Finally, the test results are also compared with electrostatic ion wind cooling with EHD cooling. The results reveal that the heat transfer coefficient can be improved by 8.03% at the same supplying power of 3W.

並列關鍵字

Electrostatic ion-wind vibration ； ion-wind cooling ； EHD cooling

參考文獻

[14] Lin, C. H., “Applied to the heat and humidity affect the centralized heat source for the electro-hydraulic power,” Master thesis, National Yunlin University of Science and Technology, Taiwan, 2014.

[4] Marco, S. M., and Velkoff, H. R, “Effect of Electrostatic Fields on Free Convection Heat Transfer from Flat Plate,” ASME Paper, N. 63-HT-9, 1963.

[6] Owsenek, B. L., Seyed-Yagoobi, J., and Page, R. H., “Experimental Investigation of Corona Wind Heat Transfer Enhancement with a Heated Horizontal Flat Plate,” Journal of Heat Transfer, Vol. 117, pp. 309-315, 1995.

[7] Owsenek, B. L. and Seyed-Yagoobi, J., “Theoretical and Experimental Study of Electrohydrodynamic Heat Transfer Enhancement through Wire-Plate Corona Discharge,” Journal of Heat Transfer, Vol. 119, pp. 604-610, 1997.

[8] Li, H. Y., Huang, R. T., Sheu, W. J., and Wang, C. C., 2007, “EHD Enhanced Heat Transfer with Needle-Arrayed Electrodes,” IEEE paper, pp.149-154, 2007.