於多數生物系統上彈液動潤滑機制能保護軟組織免於外部傷害或磨損，胸膜表面間的運動即為其中一種，胸膜表面間的運動受到呼吸運動或是外部環境影響而產生不同的潤滑機制，因此維持正常的胸膜表面運動備受關注。
較少人針對胸膜的材料特性進行討論，為了更接近於生物軟組織的特性，本研究針對改變橫向等向性胸膜的各個材料特性及其他相關參數對潤滑結果的影響進行討論。藉由耦合雷諾方程式、線性彈性方程式和負載平衡方程式來進行求解，探討不同參數變化對軟彈液動潤滑結果的影響，同時加入流體黏性剪切力，計算胸膜表面間的摩擦係數。
經模擬結果發現，對於生物軟組織或是楊氏係數較低的軟材料而言，黏性剪切力產生的影響非常顯著，不能將此效應忽略。相較於一般彈液動潤滑分析，軟彈液動潤滑分析會因材料產生大變形而使流體壓力分佈於出口區不會有壓力突起(pressure spike)的產生。對於摩擦係數而言，負載和速度對摩擦係數的相關性最高，黏度和軸向楊氏係數中等相關，而橫向楊氏係數、橫向蒲松比和軸向蒲松比則影響較小。透過本研究的分析結果，期望能做為日後呼吸學及胸腔方面相關症狀或疾病的重要參考依據。

A soft elastohydrodynamic lubrication (EHL) model for a thin layer of fluid separating the transversely isotropic pleural surface from a rigid cylinder with an initial sinusoidal shape is presented. We consider the fluid viscous shear stress and discuss the fluid pressure, fluid thickness distribution, elastic deformation of pleura and coefficient of friction for various independent variables: Young’s modulus, Poisson’s ratio, viscosity, velocity and normal load. A finite element method (FEM) is utilized to solve the modified Reynolds equation, elasticity deformation equation and force balance equation simultaneously on a line contact soft EHL problem. The simulation results reveal that coefficient of friction is strongly dependent on normal load and velocity moderately dependent on the pleural viscosity and axial Young’s modulus, and weakly dependent on transverse Young’s modulus, transverse Poisson’s ratio and axial Poisson’s ratio. These characteristics are helpful to further investigate the biomechanical interactions between pleural surfaces with multilayer and viscoelastic properties.

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