表面粗糙度對於有限長部份頸軸承 動態負荷擠壓性能之影響

Effects of Surface Roughness on the Dynamic Squeezing Behavior of Partial Journal Bearing with Finite Width

李采芬(Tsai-Fen Li)

指導教授 ： 林昭仁 ； 許政行

中原大學/工學院/機械工程研究所/碩士(2002年)

https://doi.org/10.6840/cycu200200336

摘要

本文探討表面粗糙度效應對有限長部份頸軸承的動態負荷擠壓膜性能之影響。首先由連續方程式和動量方程式，推導出雷諾方程式。考慮粗糙度為一常態分佈型式，選擇一近似高斯分佈之多項式的隨機薄膜厚度函數，運用隨機理論模式，將擠壓薄膜厚度視為一隨機變量，進而推導出縱向、及橫向及均勻等向粗糙度之隨機雷諾方程式。將隨機雷諾方程式以有限差分法展開，並以共軛梯度法(Conjugate Gradient Method, CGM)求解動態擠壓薄膜之壓力分佈，進一步求解液動擠壓薄膜作用力；再以四階朗吉-古塔法(Runge-Kutta Method)求解運動方程式，可得頸軸之速度、偏心率比、最大偏心率在不同粗糙度、時間和不同蘇馬費數(Sommerfeld number)之關係。

關鍵字

表面粗糙度 ； 頸軸承

並列摘要

The objective of this paper is to study the effects of surface roughness on the dynamic squeezing behavior of partial journal bearing with finite width. First, the Reynolds’ equation can be derived from the continuity equation and the momentum equation. By considering the roughness as a normal distribution, one can choose a polynomial approximate function as the stochastic film thickness to simulate the Gaussian height distribution. Then, by using the theorem of the stochastic models, longitudinal, transverse and uniform isotropic roughness types of stochastic Reynolds’ equation can be obtained.
After that, the stochastic Reynolds’ equation is expanded by the scheme of finite difference and then, the Conjugate Gradient method (CGM) was applied to solve the pressure distribution of dynamic squeezing film numerically; further, the force working on the hydrodynamic squeezing film can be obtained by integration. Finally, solving the Reynolds’ equation of motion by using the fourth-order Runge-Kutta method, the relationship between velocity, eccentricity and the max eccentricity of journal at different roughness parameters, time-dependent oscillating load and Sommerfeld number are acquired.

並列關鍵字

journal bearing ； surface roughness

參考文獻

[1] Jan Lundberg. Influence of surface roughness on normal-sliding lubrication. Tribology International 1995；28：317-22.

[2] Tonder K. Dynamics of rough slider bearing: effects of one-sided roughness/waviness. Tribology International 1996；29：117-22.

[3] Gurajan K, Prakash J. Effect of Surface Roughness in Infinitely Long Narrow Porous Journal Bearings. ASME Journal of Tribology 2000；121：139-47.

[4] Gurajan K, Prakash J. Effect of Surface Roughness in a Narrow Porous Journal Bearing. ASME Journal of Tribology 2000；22：472-75.

[6] 賴全、許政行、林昭仁.”表面粗糙度效應對於無限長部份頸軸承動態負荷擠壓性能之影響”.中原大學機械工程研究所碩士論文；89年6月。