本研究係以探討當固定填充率後，因不同軸向深度及轉動速度，影響由顆粒尺寸差異所導致之分離現象，同時藉由單眼相機記錄下完整實驗過程，並以程式軟體量化實驗數據，得以科學方式探究其複雜之機制。 實驗結果顯示，在較小的軸向深度且不同轉速下，分離的現象會隨著轉動速度提高，而由正分離轉至混合態，最終達到逆分離；但當在較大的軸向深度時，分離的現象則會隨著轉動速度提高，而由正分離轉至雙分離，最終才會形成逆分離。且由顆粒濃度隨時間之變化，也可以發現在較小的深度與較大的深度之間會有所差異，前者，顆粒濃度變化較為輕微；而後者，則會有較劇烈的顆粒濃度變化，這兩者的差異更凸顯軸向深度對於本研究影響之重要性，而不同軸向深度，因填充率所形成的空隙空間並不相同，進而影響顆粒運動之空間，使得軸向深度與顆粒間的交互作用，在軸向深度達到一定之臨界值以內，會有著不可分割的關聯性。 同時利用分離指標數值將各種分離現象量化，最後藉由顆粒速度場之分析，觀察轉鼓內部之顆粒運動情形，同時將其扣除轉鼓速度，可以看出在相同轉動速度下，不同深度的轉鼓內顆粒運動情形類似；而在相同軸向深度下之不同轉動速度，則會在轉鼓右上角的顆粒崩塌區域有所不同，進而影響顆粒體在其中的速度分布。;The purpose of this research is to investigate the segregation pattern and phenomena of binary-sized mixtures in a double-walled rotating drum. In this study, the effects of rotation speed and axial length of rotating drum were discussed by experimental method. The digital camera and the high speed camera were used to record the experiment process. The particle concentration and segregation degree were analyzed and discussed by digital camera in this research. Four different kind of segregation pattern could be found: positive segregation, reverse segregation, double segregation and the mixing state. We found that the segregation index will decrease with increasing rotating speed. The steady state will shift from positive separation to reverse separation with increasing rotating speed. Moreover, the transition regime includes double segregation or mixing state, depending on the drum depth. The images from the high speed camera were used to analyze the velocity field of particles in the double-walled rotating drum. The streamwise particle velocities observed at different radial positions are almost equal to the tangential velocity of the boundary of the rotation drum. However, the phenomenon has a little difference at the upper-right corner. Particle velocity in this area will be discussed.
