本研究將電濕潤（electrowetting）的原理應用於冷凝板表面，利用共平面式（coplanar）的非對稱電極設計，製造出能使冷凝液滴往單一方向排開的致動表面，主要的驅動方式為利用單一方波訊號在兩非對稱電極之間所產生的不對稱電濕潤現象（asymmetric EWOD），提供冷凝液滴在一開放平面上持續移動的機制。本研究將冷凝板分成未通入訊號前的均質冷凝板與通入訊號驅動後的電濕潤冷凝板，並比較出不同大小的驅動電極在電濕潤冷凝板上的排開效果，配合研究中所設計的冷凝實驗系統，探討各種冷凝板之熱傳效率。由實驗結果發現當G=900μm、F=1Hz、V=300Vpp時，冷凝表面具有快速排開液滴的效果，並由所設計的熱傳實驗中計算出電濕潤冷凝板比均質表面冷凝板的熱通量高出了18％左右，顯示出本研究所設計的致動表面對於熱傳量有提升的效果。藉由本研究中的驅動機制進一步的應用到各材質的冷凝板上，相信對於未來的冷凝熱傳上會有所幫助。

In this study, we applied the electrowetting principle onto the surface of the condensing plate. Using the asymmetric electrode of the coplanar design, we are able to move the condensation droplet to one direction. Between the two electrodes, asymmetric electrowetting phenomenon could be created to supply the condensation droplet continuously pumped on the open surface. The condensing plate is divided into no signal homogeneous surface and driving signal surface. First, on the driving signal surface, we compare the effect of driving with different sizes of the electrode. We also explore the heat transfer efficiency of the different condensing plate in this study. From the experiment results, we found that the surface pumps condensation droplet spontaneously when G=900μm, F=1Hz, V=300Vpp. The heat transfer efficiency increased 18 % more than the no signal homogeneous surface. This mechanism shows it enhances heat transfer efficiency truly. With our driving mechanism to the condensing plate, we believe it will be helpful for the future.

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