在微觀情況下非等向性滑移邊界條件是不可忽視的因素，由於擁有不同方向上的影響，它將會改變軸承的性能。而在考慮襯套為非剛體的情況下，材料的彈性變形量亦是重要的考慮因素，它將會影響到油膜厚度的部分。此外，工程實際的運作上不希望因為高轉速、高負載或是其他因素導致頸軸承的不穩定性，危及整個機械系統的安全運行，因此軸承穩定性的分析研究是相當重要的。
本文使用含非等向性滑移邊界條件的修正型雷諾方程式並考慮彈性變形量δ的影響，以給定負載的方式求出偏心比與姿態角計算軸承性能。而修正型雷諾方程式則使用微擾法來線性化以進行穩定性分析。將推導獲得的穩態與動態方程式透過有限元素法求解得到不同變因之下(楊氏模數、轉速、負載、不同滑移方向及滑移長度)的臨界質量變化。
結果表明在短軸承中襯套楊氏模數越大時，軸承的穩定性下降，而在長軸承中襯套楊氏模數越大時，穩定性則會提高。當提高轉速時，軸承的穩定性會稍微下降，並且楊氏模數對臨界質量的影響逐漸無關。而在考慮非等向性滑移邊界條件的影響時，發現在細長比大於1的軸承中移動表面或靜止表面的y方向滑移，可以提高軸承的臨界質量，並且隨著細長比增加y方向滑移對臨界質量提高的幅度更大，但是滑移效應對臨界頻率的影響則不大。當負載較小時，滑移的影響增加。

In this study, the modified Reynolds equation with anisotropic slip boundary conditions is used to analyze the stability of the modified Reynolds equation by using the perturbation method under the influence of elastic deformation. According to the real working situation, it is different from the solution of the given eccentricity ratio of the journal bearing hydrodynamic problem, but is solved by the given load. The derived steady-state and dynamic equations are solved by the finite element method (FEM), and the critical mass changes under different variables (Young's modulus, rotating speed, load, different slip directions and slip lengths) are discussed.
The results show that the slip direction of different surfaces will affect the stability of journal bearing. When the slenderness ratio is greater than 1, the sliding in y-direction on the moving surface or stationary surface is helpful to improve the stability, but the slip has little effect on the critical frequency. When the rotating speed is increased, the stability of journal bearing will decrease, and the critical mass will decrease to a certain value with the increase of the speed. The larger the Young's modulus in short bearings, the lower the stability, while the larger the Young's modulus in long bearings, the higher the stability.

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