雙壁旋轉鼓之不同轉速對顆粒分離機制之研究

NCUIR > Engineering College > Graduate Institute of Mechanical Engineering > Electronic Thesis & Dissertation > Item 987654321/81640

Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/81640

Title:	雙壁旋轉鼓之不同轉速對顆粒分離機制之研究
Authors:	黃柏翰;Huang, Po Han
Contributors:	機械工程學系
Keywords:	雙壁轉鼓;顆粒體;填充率;轉速;尺寸分離;double-wall drum;particles;fill rate;rotation speed;size segregation
Date:	2019-07-24
Issue Date:	2019-09-03 16:34:47 (UTC+8)
Publisher:	國立中央大學
Abstract:	本研究是以雙壁旋轉鼓為實驗設備，並以實驗的方式分別針對在不同的填充率以及轉速下，探討轉鼓中顆粒的尺寸分離現象。實驗結果顯示：以混合狀態開始旋轉，當固定轉速由最低開始逐漸增加時，顆粒的最終分離狀況起初會維持小顆粒在外而大顆粒在內的正分離狀態，直到轉速超過某個臨界值時，顆粒的分離狀態會馬上變成混合，而此時再繼續提高實驗的固定轉速，分離狀況則會隨著轉速漸漸由混合至逆分離狀態。而不同填充率之下，填充率降低則會使正分離狀態與混合狀態間的臨界轉速跟著降低。本實驗也使用高速攝影機來捕捉顆粒的運動速度，而其結果顯示當分離現象為正分離、混和或是逆分離，皆有與其他現象不同的顆粒擾動最集中之位置。正分離時其顆粒擾動最劇烈的地方靠近轉鼓外壁，且其擾動程度也是最集中且最大的；而混合狀態其擾動最烈之處集中在外壁與中間之間的地帶，其擾動程度則不大；逆分離的則是集中在內圈與中間之間的地帶，擾動程度與混合狀態相近。;A double-wall rotating drum was used to investigate segregation phenomena in this research. The effects of fill rate and rotation speed on segregation index in the rotating drum were discussed by experimental method in the paper. The steady state value of segregation index remain the same which represent the small particle located on inside and big particle on outside when the rotation speed is low. As the rotation beyond the critical value, the segregation phenomena would change to mixing state. After that, segregation index decrease with the increase of rotation speed. The critical value of rotational speed would decrease when fill rate decrease. A high-speed camera was used to capture the velocity field in this research. The result shows that when segregation index was approximately to 1, the fluctuation of particles would concentrate at the tiny area which located on nearly the outside wall of the drum. The level of that fluctuation was also very high. When segregation index was approximately to 0, the fluctuation of particles would concentrate at the area which located on the zone between outside wall and the middle. When segregation index was between 0 and -1, the fluctuation of particles would concentrate at the area which located on the zone between the middle and inside wall.
Appears in Collections:	[Graduate Institute of Mechanical Engineering] Electronic Thesis & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	107	View/Open

社群 sharing

Loading...