由於科技的發達，人類的生活獲得了相當程度的改善，一方面增加了人類的平均壽命，但一生中疾病對人類健康的危害也相對的增加。許多研究顯示，血管疾病是人類健康的最大敵人。根據臨床實驗顯示，動脈病變如動脈粥狀硬化（atherosclerosis）和血栓形成（thrombosis）最常發生在血管分歧與彎曲等特定區域，研究證據亦顯示動脈病變的發生與這些區域中，如流動分離(flow separation)、二次流(secondary flow)、渦流(vortex)等血流特定流場有直接關聯。
腹主動脈分歧眾多，其主要的分枝有腹腔動脈幹、上腸繫膜動脈、左右腎動脈、下腸繫膜動脈，左右髂總動脈等。承繼前一系列之研究，在本文中，係針對不同入口條件對腹部主動脈流場的影響做一系列的探討與模擬，並將流場的速度分佈、剪應力（率）分佈、迴流區位置及參數s的分佈情形做一系列的觀察與討論。

Many studies have shown that the arterial diseases have been one of the most life-threatening diseases. According to the clinical data the locations where arterial diseases tend to develop are those special areas such as branches and bend of aorta. The blood flows in these areas usually contain flow separation, secondary flow or vortex. Many studies show that these complicated flow fields are directly related with arterial diseases.
In the present study, the effect various inlet conditions on the flow field of the abdominal aorta are simulated. The velocity profiles and distribution of the wall shear stress and location of flow reversed region are presented.

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