軸承常見於機械裝置，在軸承系統的設計分析中，精確估算軸承性能參數是一項非常重要的工作，例如軸承負載量、摩擦力係數和離心角度等。由文獻中可知，頸軸承在牛頓潤滑己被充分研究，對於非牛頓潤滑，研究都集中在等溫層流和熱液動力層流(THD)領域，但目前對紊流潤滑領域，包括等溫或THD都還沒有充份研究。
研究目的以奈威爾-史托克方程式為基礎，發展非牛頓流熱液動力頸軸承模式，分析全包覆式無限寬頸軸承非牛頓對性能參數之影響。此模式以Shyu和Jeng發展的EGFLUM模式為基礎，壓力從容積流模式解得，速度和溫度由Legendre collocation方法求得，孔蝕效應由Elrod’s孔蝕演算法來處理，非牛頓流模式採用冪次模式。與Shyu和Jeng研究不同之處在於他們使用SIMPLE演算法解容積流方程式，而本研究是採用SIMPLER演算法。
從結果得知，軸承的性能參數在非牛頓型態是跟牛頓型態有明顯的差異，當冪次指數n大於1時，壓力、負載、摩擦係數會比牛頓流大，因為受到稠化性影響，當冪次指數n小於1時，受到稀化性影響，壓力、負載、摩擦係數會降低。

Bearings are usually used in many mechanical equipments. To design a bearing system, it is desirable to have accurate values of performance parameters such as the load capacity, friction coefficient and eccentricity angle. For the journal bearings with non-Newtonian lubricants, most researchers focused on the laminar isothermal and laminar thermohydrodynamic (THD) regimes. It is not fully understood for the turbulent isothermal and turbulent THD regimes.

The objectives of this study are to develop a non-Newtonian THD model for journal bearings based on the Navier-Stokes equations and to study the effects of non-Newtonian on the performance parameters for infinitely wide full journal bearings. The model is based on the EGFLUM model developed by Shyu and Jeng, in which the pressure is solved using the bulk-flow model and the velocity and temperature are solved using Legendre collocation method. Elrod's cavitation algorithm is implicated to model the effects of cavitation, and the power-law model is used to model the non-Newtonian fluid. In contrast to the study of Shyu and Jeng, who used SIMPLE algorithm to solve the bulk-flow equations, the SIMPLER algorithm is used in this study.

From the results, it is found that the values of the bearing performance parameters for the non-Newtonian fluids are significantly different from those for the Newtonian cases. When the power-law index n is greater than unity, the pressure, load capacity and friction coefficient will become larger than those for the Newtonian flow due to the shear thickening effects. When n is less than one, the shear thinning effects result in the decrease in the pressure, load capacity and friction coefficient.

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