本文以數值方法研究層流預混火焰在封閉圓管內的傳播行為。文中
，所考慮的流場為軸對稱， 並採用單步驟，反應速率遵照 Arrhenius 定
律的化學反應，來探討初始高溫熱塊厚度，重力場，以及邊界條件對火焰
傳播的影響。 數值分析結果顯示，在封閉圓管中，吾人可以觀察到鬱
金香形、蕈狀形或是介於兩者之間的火焰形狀，至於形成何種形狀的火焰
與問題的條件有關。 計算結果表明了火焰本身引發的流體流動是影響
火焰形狀的主要因素之一。

In this study, we employ the numerical method to study
the propagationbehavior of a premixed laminar flame in a
closed circular tube. Anaxisymmetric flow is considered, and
a one-step overall reaction with reactionrate governed by
Arrhenius law is used to study the effects on the
flamepropagation of the thickness of the initial hot spot,
the gravity, and theboundary conditions. The numerical
results show that a tulip-shaped flame, a mushroom-shapedflame
or a flame with a shape between them will exist in the small
closedcircular tube, depending on the given conditions. The
results indicate that one of the factors controlling the flame
shapeis the flow field of the mixture induced by the flame.