臺灣博碩士論文加值系統

本研究以實驗分析含人字形溝槽之液體動壓頸軸承應用於離心散熱風扇的振動與噪音特性。軸承溝槽參數設計以前人對動壓軸承溝槽尺寸之數值模擬文章所提出最佳化設計數據作為參考，設計並加工出數種不同溝槽的軸承，藉此分析不同溝槽參數對於振動與噪音之影響。實驗部分將以壓電式加速度規來量取風扇運轉時所產生的振動，並以振動信號作為穩定性的參考，此外以提供之電源功率來觀察轉子因與潤滑油膜摩擦所散失的能量。噪音實驗部分於半無回響室中量取風扇運轉時所產生之噪音，並由聲音壓力位準以及聲音品質兩種角度來評判軸承在噪音上的表現。
實驗結果顯示，軸承的穩定性在溝槽深度比為1、溝槽角度40度、溝槽數8時為最佳。而風扇的噪音和軸承的徑向振動量有正相關，建議將軸承的深度比設計在1.5~2之間以降低風扇之噪音量。

The objective of the study is to investigate the vibration and noise characteristics of hydrodynamic journal bearing with herringbone groove use for centrifugal fan. The design parameters of groove refers to the paper which is about the optimization design of groove. The bearings are made with different types of grooves for the purpose of analyzing the influence of deign parameters on vibration and noise. The vibration measured by piezoelectricity accelerometer will be the reference of the stability of bearing. And the power loss made by the friction between shaft and liquid-lubricated film will be observed by the supply power of fan. The fan noise is measured in the half anechoic chamber, and judge the noise performance from sound pressure level and sound quality.
The results show that the optimum groove parameters based on the stability criteria are: the groove ratio is 1, the angle is 40 degree, and the numbers of grooves are 8. And the noise of fan correlates to the axial vibration of fan, so the suggestion of groove depth ratio for reducing the noise is 1.5~2

目錄
致謝 I
摘要 II
Abstract III
圖目錄 VII
表目錄 X
符號說明 XI
第一章序論 1
1.1 研究背景 1
1.2研究目的 2
1.3文獻回顧 3
1.4研究方法 4
第二章 風扇振動與噪音量測實驗原理 6
2.1 軸承振動源分析 6
2.2 軸承表現評判之分析 7
2.2.1 風扇運轉所消耗之功率 7
2.2.2 軸承穩定性之分析 8
2.3 風扇噪音源之分析 10
2.4 風扇噪音表現評判之分析 10
2.4.1 以聲音位準評判風扇噪音表現 11
2.4.2 以聲音品質評判風扇噪音表現 12
第三章 實驗架構與方法 15
3.1 軸承之設計與風扇之組裝 15
3.2 轉子之殘留不平衡質量 17
3.3 振動量測實驗架構 17
3.4 振動量測之實驗步驟 19
3.5 噪音量測實驗架構 20
3.6 噪音量測之實驗步驟 21
第四章 實驗結果與分析 23
4.1風扇葉片試品之選擇 23
4.2 軸承頻譜分析 23
4.3 振動量測結果 24
4.3.1溝槽深度比對於軸承之影響 24
4.3.2溝槽角度對於軸承之影響 26
4.3.3溝槽數目對於軸承之影響 27
4.3.4 振動實驗與數值模擬穩定性之比較 28
4.4 風扇噪音量測結果 29
4.4.1 軸承溝槽深度比對於風扇噪音之影響 29
4.4.2 軸承溝槽角度對於風扇噪音之影響 31
4.4.3 軸承溝槽數對於風扇噪音之影響 31
4.5 實驗數據誤差分析 32
第五章 結論與建議 34
參考文獻 73

Asada, T., Saitou, H., Asaida, Y., Itoh, K., 2001, “Characteristic Analysis of Hydrodynamic Bearing for HDDs,” IEEE transactions on magnetics, 37(2), pp. 810-814.
Gao, F., Yan, Y., Yap, F., 2003, “Vibra-acoustic interaction of components in hard disk drive under seek process,” Microsystem Technologies, 9, pp. 496-500.
Hamrock, B.J., 1994, “Fundamentals of Fluid Film Lubrication,” McGraw-Hill, New York, pp. 141-290.
Matsuoka, K., Obata, S., Kita, H., Toujou, F., 2001, “Development of FDB Spindle Motors for HDD Use,” IEEE transactions on magnetics, 37(2), pp. 783-788.
Jang, G.H., Chang, D.I., 2000, “Analysis of a Hydrodynamic Herringbone Grooved Journal Bearing Considering Cavitation,” ASME Journal of Tribology, 12w, pp. 103-109
Jang, G.H., Kim, Y.J., 1999, “Calculation of Dynamic Coefficients in a Hydrodynamic Bearing Considering Five Degrees of Freedom for a General Rotor-Bearing System,” ASME Journal of Tribology, 121, pp. 499-505.
Jang, G.H., Yoon, J.W., 2002, “Dynamic characteristics of a coupled journal and thrust hydrodynamic bearing in a HDD spindle system due to its groove location,” Microsystem Technologies, 8, pp. 261-270.
Jang, G.H., Yoon, J.W., 2002, “Nonlinear Dynamic Analysis of a Hydrodynamic Journal Bearing Considering the Effect of a Rotating or Stationary Herringbone Groove,” ASME Journal of Tribology, 124, pp. 297-304.
Jintanawan, T., Shen, I.Y., Tanaka, K., 2001, “Vibration Analysis of Fluid Dynamic Bearing Spindles with Rotating-Shaft Design,” IEEE transactions on magnetics, 37(2), pp. 799-804.
Park, J.S., Shen, I.Y., Ku, R., 2002, “A parametric study on rocking vibration of rotating disk/spindle systems with hydrodynamic bearings: rotating-shaft design,” Microsystem Technologies, 8, pp. 427-434.
Wan Junmei, T.S., Lee, C.S., Wu, J.K., 2002, “A Numerical Study of Cavitation Foot-Prints in Liquid-Lubricated Asymmetrical Herringbone Grooved Journal Bearing,” Int. J. Numerical Methods for Heat&Fluid Flow, 12, pp. 518-540.
Zang, Y., Hatch, M.R., 1995, “Analysis of Coupled Journal and Thrust Hydrodynamic Bearing using Finite-Volume Method,” ASME Advance in Information Storage and Processing System, 1, pp. 71-79.
Zhang, Q.D., Winoto, S.H., Chen, S.X., Yang, J.P., 2002, “A bi-directional rotating fluid bearing system,” Microsystem technologies, 8, pp. 271-277.
Zirkelback, N., Andres, L., 1998, “Finite Element Analysis of Herringbone Groove Journal Bearing :A Parametric Study,” ASME Journal of Tribology, 120, pp. 234-240.
張珈進, 2003, “寬頻元素法應用於液體動壓軸承之研究,” Master thesis, Dept. of Mechanical Engineering, NTU, Taipei, Taiwan.