| 摘要: | 當旋轉機械系統內部的轉動件具有不平衡質量時，在轉動過程中會引起振動，
長久下造成機械系統產生噪音損害與降低使用壽命。本研究將顆粒阻尼器應用於
引擎轉軸來校正動平衡狀態，同時顆粒阻尼器中顆粒與壁面間的碰撞與摩擦抑制
旋轉機械系統的振動，達到動平衡校正兼具抑制振動的效果，為探討顆粒阻尼器對
抑制振動的效益，實驗中設計等效質量無顆粒阻尼器引擎轉軸與具顆粒阻尼器引
擎轉軸，在兩者皆達到動平衡校正至ISO1940 動平衡規格G2.5 等級以下，且達相
近的動平衡允許值後，比較等效質量無顆粒阻尼器引擎轉軸與具顆粒阻尼器引擎
轉軸的動態反應，探討工作轉速、負載扭矩與顆粒粒徑對引擎轉軸動態反應的影響，
其中分析的動態反應物理量包含時域訊號中加速度的方均根值、頻域訊號中的功
率譜密度與單位質量的動能。
研究結果顯示： (1)在頻域訊號的比較中，各轉速下功率譜密度與單位質量的
動能的一倍頻率中，具顆粒阻尼器引擎轉軸相較於等效質量無顆粒阻尼器引擎轉
軸皆來得低，說明具顆粒阻尼器引擎轉軸兼具動平衡校正與抑制振動的效果； (2)
透過振動訊號分析，觀察工作轉速與負載扭矩對引擎轉軸動態行為的影響，在低轉
速及低扭矩、高轉速及高扭矩的組合中，各粒徑顆粒阻尼器引擎轉軸相較等效質量
無顆粒阻尼器引擎轉軸的振動降幅比具有顯著的減振效果，但φ4 mm 顆粒阻尼器
引擎轉軸在高轉速及高扭矩的組合中，減振效果呈現降低的趨勢； (3)透過振動訊
號分析，觀察顆粒粒徑對引擎轉軸的影響，探討的粒徑包含φ2 mm、φ3 mm 與φ4
mm，其中φ2 mm 顆粒阻尼器引擎轉軸具有最穩定且顯著的抑振表現； (4)通過本
實驗驗證，在顆粒阻尼器中填充適當粒徑的顆粒，並做好動平衡校正，可有效降低
引擎轉軸的振動。;When the rotating parts inside the rotating mechanical system have an unbalanced
mass, vibration will be caused during the rotation process, leading to noise damage and
reducing service life of the mechanical system in the long run. In this study, a particle
damper is applied to the engine shaft to correct the dynamic balance state. At the same
time, the collision and friction between the particles and the wall in the particle damper
suppress the vibration of the rotating mechanical system, achieving the effect of dynamic
balance correction and vibration suppression. To explore the effectiveness of particle
damper in suppressing vibrations, the engine shafts designed with equivalent mass
without particle dampers and the engine shafts with particle dampers both achieved
dynamic balance correction to the G2.5 level in ISO1940 dynamic balance specification,
attaining similar dynamic balance allowances. After dynamic balance, the dynamic
response of the two kinds of engine shafts were compared, and the effects of operating
speed, load torque and particle size on the dynamic response of the engine shaft were
systematically explored. The dynamic physical properties include the root mean square
value of the acceleration in the time domain signal, the power spectral density and energy
in the frequency domain signal.
The research findings are summarized below: (1) In the comparison excitation
frequency of frequency domain signals, at each speed, the power spectral density and
energy of the engine shaft with particle dampers are lower than those in the engine shaft
with equivalent mass without particle dampers, showing that the particle damper provides
the effect of vibration suppression; (2) At low speed with low torque and high speed with
high torque, the engine shaft with particle dampers relative to the engine shaft with
equivalent mass without particle damper has a significant vibration reduction effect.
However, at low speed with low torque, the vibration reduction effect of particle damper
with 4 mm particles shows a decreasing trend; (3) The effect of particle size was explored
and three kinds of particle diameters (2 mm, 3 mm and 4 mm) were used. The particle
damper with 2 mm particles exhibits the most stable and significant performance in
vibration suppression; (4) Through experimental validation, by using particles of
appropriate particle size and conducting dynamic balance correction, the particle dampers
can reduce the vibration of the engine shaft effectively. |
