隨著近代醫學越來越發達，與人體健康之相關之研究變得越來越多，其中一樣人體每天都需要的事情就是運動。而與運動最息息相關的人體構造即為關節軟骨(articular cartilage)，他在人體的動關節中扮演緩衝力量並保護硬骨之間的接觸。關節軟骨具有極為特別的層狀結構以及孔隙構造，孔隙中富含關節潤滑液(synovial fluid)，使其具備極為良好的磨潤性質，能夠承受人體長時間下各種不同的擠壓、摩擦等等不同運動形式。尤其近幾年來關節置換物成為了新的一項熱門的研究，而為了讓人工關節能夠達到與人體自然關節相同的性能勢必會對這方面進行更深的研究。
在本研究中我們探討一剛球進行定負載純擠壓下方之關節軟骨，而關節軟骨中包含了上層之孔隙層以及下層之彈性層，利用有限元素分析法模擬分析擠壓時對潤滑液造成之壓力、膜厚、變形等等性質以及電雙層效應進行探討。從結果中可以得到關節軟骨之滲透率、孔隙厚度、Inverse Debye length及電黏度等等對關節軟骨在擠壓時所造成的影響，綜合討論各項參數之結果並進一步進行統整後能夠歸納出接近於真實軟骨在運動時之情形，並且在之後不管是了解關節軟骨的潤滑性以及未來在進行人工關節的製備上都會有更多的參考依據。

With the medical field developed, human life become longer, whether articular cartilage is healthy or not become an important issue for longer using. Articular cartilage have a special layer structure and pore with synovial fluid inside, make it have a great grinding performance, which can support variety of loading or motion in different movement for a long time. In this research we equivalent the motion of articular cartilage into a rigid ball with constant load pure squeeze action. Using modified Reynold equation considering electric double layer effect and film equation, force balance equation, Using finite element analysis to simulate and couple these governing equations. The influence of permeability, pore thickness and electric double layer effect can be mainly discussed in the results. The apparent viscosity will increase when permeability decrease, pore thickness increase or electric double layer effect increase, with this model we can figure out the effect between these variable with pressure, film thickness and apparent viscosity.

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