軟彈液動潤滑是生物磨潤系統中非常重要的問題，軟組織藉由有限的大變形來減少相對運動的表面之間的摩擦和破壞。傳統(硬)彈液動與軟彈液動潤滑的數值計算方法存在著些差異，傳統彈液動缺乏將“軟”的關鍵特徵考慮在數值計算的模型分析。
本文將建立軟彈液動潤滑的線接觸模型的數值計算方法，材料尺寸以有限厚度取代彈性半空間假設並考慮材料幾何非線性及有限應變理論。流體表面速度則考慮受到材料有限變形引起的曲率效應。數值計算是藉由有限元素法分析各種表面夾帶速度、材料楊氏係數及不同條件參數下討論流體壓力、流體薄膜厚度和材料變形及應力分布。在軟彈液動潤滑和硬彈液動潤滑建模假設進行比較，之後再考慮生物軟組織的橫向等向性的特性，在各種楊氏係數及蒲松比的組合下，討論流體壓力、流體薄膜厚度和材料的變形及應力分布，獲得橫向等向性材料最佳的參數組合。
分析結果表明傳統彈液動潤滑不適用於高負載及低楊氏係數材料，軟彈液動潤滑模型更符合現實的結果。在接觸區域中，傳統彈液動計算模型會高估壓力分佈而低估膜厚和變形，軟彈液動潤滑模型具有更平緩的應力分佈。因此，本研究所建立的軟彈液動潤滑模型能幫助軟材料在設計上的參考依據。

Soft elastohydrodynamic lubrication (soft-EHL) is an important topic in the biotribological system. The finite deformation of soft-EHL in the biological tissues can decrease the friction and failure which are in the relative moving surfaces of the tissues. The numerical calculation of classical EHL (hard-EHL) doesn’t consider enough for the factors of soft tissue features in the finite element method.
In this paper, a complete soft-EHL linear-contact model is developed. In the model, the elastic half-space is replaced by the finite thickness analysis and considers geometric nonlinearity as well as finite strain theory. The surface velocities altered by the curvature effect are considered, and the load balance equation is formulated based on the deformed configuration. The film thickness, pressure distributions, and material deformation are analyzed under various entraining velocities, elastic modulus, and material thickness of the soft layer. Furthermore, the results can compare between soft-EHL and hard-EHL modeling assumptions. The analyses show that hard-EHL method is inappropriate on high load and low elastic modulus, and the soft-EHL model can be more accessible and reality.
In the contact region, the hard EHL solver overestimates the pressure distribution and underestimates the film thickness and deformation affection. For the soft-EHL model, it can obtain smoother distribution of stress. Therefore, the soft-EHL model from this research can be a reference for the soft material design in the future.

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