溼度改變是影響顆粒體運動的主因之一，因此溼度對顆粒體的影響已經受到許多學者的重視。本論文以實驗的方式研究不同溼度下顆粒體於垂直振動時所形成堆角的變化。觀察以不同的振動加速度配合不同的相對溼度對顆粒堆積的影響，並對結果作深入的探討。
本實驗以導入蒸氣的方式控制溼度，首先固定相同的溼度，改變不同的振動加速度觀察堆角的變化。接著再改變溼度觀察溼度對堆角的影響。結果顯示，當振動加速度到達某個特定值時顆粒會有較大的堆積角。而溼度方面，實驗的結果也顯示當溼度變化時，顆粒的堆積角會有先增後減的變化。

Variable humidity is the main factor to affect the behaviors of granular materials. In this study, experimental method is used to investigate the variations of heaping angles with different humidity in the vertical vibrated granular bed. At the same time, vibrating acceleration is also changed to obtain the granular heaping. To control the humidity inside the closed bed system, water vapor is induced into the bed by a vacuum motor and many valves. The heaping angle of granular materials increase initially with increasing humidity, however, it decrease with increasing humidity after the relative humidity approaches 37%. On the other hand, heaping angle become larger when the vibrating acceleration has been over somewhat value.

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