本次研究以計算流體力學為工具，在三維T型管微混合器中利用冷牆和熱牆的溫度差所產生的自然對流，來探討浮力對混合效率的影響。研究結果顯示，在T型管主流道中，因浮力而產生的漩渦其會隨冷熱牆的溫度差增加而增強，而此漩渦在待混合流體間之接觸面有拉伸捲曲的作用，因此接觸面面積變大有助於混合效率增加。同時漩渦的渦度越強，表示T型管截面上的速度分量越大，截面上待混合流體間的對流現象越旺盛，也有助於混合效率的提升。

The effect of buoyancy on the mixing efficiency of a T-tube micromixer is studied in this work using computational fluid dynamics. Natural convection generated by the temperature difference between the cold side wall and the hot side wall of the T-tube main channel will induce a vortex whose core is roughly in parallel to the main channel axis. This vortex generates cross-sectional velocity components which are advantageous to the mixing efficiency in two aspects. First, the mixing interface will be stretched and elongated by the cross-sectional velocity, and consequently the mixing interface area will be increased. Second, the cross-sectional velocity components will cause convective flows in the direction normal to the mixing interface, which increases the mixing efficiency.

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