本研究使用數值方法來模擬新生兒先天性心臟疾病之一的法洛氏四重症，針對分歧肺動脈內之流場型態分析。利用改變不同的主肺動脈倒流率比(b/f)此參數來模擬不同的狀態，觀察肺動脈內之流場型態的變化，並分析左右肺動脈之倒流率與淨流量的數值結果。在醫院所量測到的數值來看，發現左肺動脈倒流率會比右肺動脈高。而本研究目的是利用數值方法解析肺動脈中的流場變化，進一步說明其結果之原因。
在此利用流場型態來分析，因左肺動脈皆會比右肺動脈早產生倒流之情形，且左肺動脈倒流經過時間也較久，所以可得知左肺動脈倒流率高於右肺動脈。利用所計算出的數值可得知，若是提高主肺動脈倒流率，亦即倒流較嚴重的情況下,左右的肺動脈倒流率也隨之增大。在本研究利用數值方法以及醫學所量測的數據中，左肺動脈倒流率值(b/f)是比右肺動脈高的。這與流場型態分佈是可相呼應的。
並且在主肺動脈倒流率很低時，發現在左右肺動脈的淨流量值相差很小。反之，當主肺動脈倒流率增大時，左右肺動脈的淨流量值相差就越大。

The aims of this study are using numerical approaches to simulate flow variations in pulmonary artery of patients of Tetralogy of Fallot, which is one of the congenital heart diseases in children. We analyze the flow patterns in an in vitro bifurcation pulmonary artery and consider effects of various regurgitation ratios(b/f) in left pulmonary artery(LPA) and right pulmonary artery(RPA). We do not only observe the variation of flow patterns, but also analyze the results of b/f and volumetric flow rates in LPA and RPA. In general, the b/f of LPA is higher than RPA in the mesured data provided by Kaohsiung veterans general hospital. We validate the result using numerical approaches to analyze the flow patterns in pulmonary artery in this study.
We use predicted flow patterns to explain why the b/f of LPA is higher than RPA. It is because the duration of regurgitation in LPA is longer than in RPA. In terms of predicted results, we can know if the b/f of main pulmonary artery(MPA) increases, so will b/fs of LPA and RPA. The b/f of LPA is higher than RPA both in this study and the mesured data of the hospital. It is consistent with the flow patterns predicted by this study. We also can find the difference of netflow between LPA and RPA is tiny when the b/f of MPA is low. On the contrast, the difference of netflow between LPA and RPA will increase if the b/f of MPA is raised.

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