間隙流體對於旋轉儀內顆粒偏析機制的影響

The effect of liquid on particle segregation mechanism in rotating drum

鄒仕豪(Shih-hao Chou)

指導教授 ： 蕭述三

國立中央大學/工學院/機械工程學系/碩士(2007年)

摘要

本研究是以類二維的精密旋轉儀為實驗設備，並以實驗的方式分別針對在不同的間隙流體含量以及不同的間隙流體黏度條件下，精密旋轉儀中顆粒的分離現象、安息角(angle of repose)角度，以及流動層厚度的研究探討。實驗結果顯示出當間隙流體含量逐漸增加的同時，安息角角度和流動層厚度也會隨之漸漸的變大，且當間隙流體的含量超過某一臨界值時，安息角角度及流動層厚度將不再改變，而趨近於一穩定值。而在分離現象方面，分離強度會隨著間隙流體含量的增大而漸漸變小，且當間隙流體的含量超過某一臨界值時，分離強度將也會趨近於一穩定值。而當我們固定間隙流體含量然後改變間隙流體的黏度時，安息角角度和流動層厚度也會隨著黏度的增加而變大，但分離強度會隨著間隙流體黏度的增加而減弱。實驗也可以得知，不管增加間隙流體的含量或是增加間隙流體的黏度，粒子的流動速度都會隨之而變慢。

關鍵字

液體含量 ； 液體黏度 ； 分離 ； 安息角 ； 流動層

並列摘要

A quasi-2D rotating drum was used to investigate segregation phenomena in this research. The effects of content and viscosity of added liquid on segregation index, angle of repose, and the flowing thickness in the rotating drum were experimental discussed in the paper.
The angle of repose and flowing thickness in the rotating drum increased with increasingly added liquid content. As the added liquid content was lager than the critical amount, the angle of repose and flowing thickness would reach a stable value.
The segregation index of mixture in the rotating drum decreased with the increase of added liquid content and that would reach a stable value as the added liquid content larger than the critical amount.
With changing the viscosity of liquid at the same liquid content, the angle of repose and flowing thickness increased but the segregation index decreased.
The velocities of particle motion in the rotating drum would be slower due to the increasingly content and viscosity of the added liquid.

並列關鍵字

flowing zone ； angle of repose ； liquid content ； liquid viscosity ； segregation

參考文獻

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4.Liu, X. Y., Specht, E., Mellmann, J., “Experimental study of the lower and upper angles of repose of granular materials in rotating drums,” Powder Technol., Vol. 154, pp. 125-131, 2005.

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