本文係使用半投射有限元素法（ FEM ）與前置處理之共軛梯度法，研究週期邊界條件下加熱塊之流道中的流場與熱對流增益。本文使用時間平均紐賽數，摩擦性能及熱性能係數來探討週期性邊界條件與不同雷諾數（100，175，250）下，在流道中如何安裝矩形柱狀物以產生增益效果。結果指出，安裝矩形柱狀物在上游加熱塊上方可以有效地強化加熱塊的傳熱；然而，增加矩形柱狀物數目會增加摩擦性能。結果發現，週期邊界條件下每兩個加熱塊安裝一矩形柱狀物具有最好的熱性能。

This paper investigates flow field and convective heat transfer enhancement in a block-heated channel with periodic boundary conditions using the element by element in semi-projection finite element method (FEM) coupled with preconditioned conjugate gradient method. This paper used time-mean Nusselt number ratio, friction performance, and thermal performance to study how installing rectangular cylinders in the channel works with periodic boundary conditions at different Reynolds numbers (100, 300, and 500). The results indicate that the rectangular cylinders mounted in cross-flow above an upstream block can effectively enhance heat transfer in the block-heated channel. However, increasing the number of rectangular cylinder can increase the friction performance. As a result, the case for periodic boundary conditions with a rectangular cylinder above the first block every two blocks has the best thermal performance.

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