- 學位論文
動壓頸軸承設計參數之性能影響分析及設計最佳化
An Investigation in the Influence of Design Parameters on the Performances of Hydrodynamic Journal Bearings and Design Optimization
摘要
本文根據動壓頸軸承國際標準文件的設計參數，探討設計參數變化帶來的影響，其中包含討論長徑比、Sommerfeld數及軸承展角的變化對於最小膜厚、偏心比、姿態角、摩擦係數、流量、壓力比及溫升等數據之影響。使用田口方法進行設計實驗，選擇合適的直交表，將潤滑油黏度、間隙、軸承長度、軸承展角及入口油溫等設計參數作為控制因子，設定不同數值水準並且填入直交表內進行運算，根據結果進行分析，以減少摩擦以及溫升為目的進行動壓頸軸承之設計參數最佳化，探討各控制因子是否有交互作用，並透過迭代選擇較佳的潤滑劑黏度型號，迭代時以內插法替換迭代法，以假設工作黏度作為x軸，計算工作黏度作為y軸，將兩次迭代的假設值與計算值作為兩點進行連線，將假設值等於計算值連線，計算兩線段交點位置，得出的溫度作為第三次猜值進行計算，若未達收斂標準則重複上述過程，使用內插法比單純迭代法更快的達到收斂標準。將環境溫度、負荷變動、速度變動、潤滑油黏度變動及潤滑油溫度變動等干擾因子列入直交表進行實驗，分析干擾因子對於軸承性能之影響。 關鍵字：動壓頸軸承、最佳化設計、田口法
並列摘要
This article investigates the effects of variations in design parameters based on the international standard documents for hydrodynamic journal bearings. The discussion encompasses changes in design parameters including aspect ratio, Sommerfeld number, and bearing angle, and their impacts on minimum film thickness, eccentricity ratio, attitude angle, friction coefficient, flow rate, pressure ratio, and temperature rise. Design experiments are conducted using the Taguchi method, employing a suitable orthogonal array. Lubricating oil viscosity, clearance, bearing length, bearing angle, and inlet oil temperature are chosen as control factors. Various numerical levels are assigned to these factors within the orthogonal array for computations. The results are analyzed to optimize the design parameters of hydrodynamic journal bearings with the goal of reducing friction and temperature rise. The study investigates potential interactions among the control factors and iteratively selects the optimal lubricant viscosity model. In the iteration process, interpolation replaces the conventional iteration method. Hypothetical working viscosity is plotted on the x-axis against calculated working viscosity on the y-axis, connecting assumed and calculated values from two iterations. The intersection point of these lines is used as the temperature for the third iteration. If convergence criteria are not met, the process is reiterated. Interpolation accelerates convergence more effectively than simple iteration. Environmental temperature, load fluctuations, speed variations, changes in lubricating oil viscosity, and variations in lubricating oil temperature are included as interfering factors in the orthogonal array for experimentation, enabling the analysis of their influences on bearing performance. Keywords: hydrodynamic journal bearings , design optimization ,taguchi method