本文主旨是以實驗方法探討氣泡的特性，藉由量測影像技術，以高速攝影機拍攝水中氣泡上升的過程，並利用影像處理進行分析，可計算出氣泡之粒徑大小、數量、體積分率及單位體積密度。本實驗在成功大學水利及海洋工程學系光纖感測及聲學實驗室之玻璃纖維水槽，將發泡器材沉入水槽底部，實驗過程中，利用空氣壓縮機輸入穩定的空氣至氣泡石軟管及陶瓷氣泡石，待氣泡穩定的從水槽底部緩慢上升一段時間，以高速攝影機每秒拍攝30張影像，記錄其上升過程，影像儲存於電腦。實驗結果發現，在低孔隙率情況下，氣泡較分散且容易判斷其粒徑大小及體積，而在高孔隙率情況下，因氣泡會互相撞擊、結合及分裂等情形，其重疊率高導致分析上容易出錯。本研究所得之實驗結果適用於低孔隙率情況，較不適用於高孔隙率。

This study aims to analyze the bubble size distribution by using the high-resolution CCD camera. The experimental setup consists of a high-resolution CCD camera, a light source, a air-bubble generator, and an air compressor. The high-quality digital images of bubbles were analyzed to obtain the characteristics of bubbles. Our study reveals that when the air volume fraction of the bubbly water is low, the proposed method can obtain accurate size distribution of bubbles. However, when the air volume fraction is high, overlapping of bubbles occurs, which makes the identification of individual bubble difficult. As a result, the obtained size distribution of bubbles may be inaccurate.

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