本研究以實驗的方式探討間接加熱式旋轉鼓於不同的旋轉速度與壁面粗糙因子下，顆粒體與覆蓋壁面間的熱傳遞係數。鋁製旋轉鼓內徑為100 mm，厚度為10 mm，實驗顆粒為2 mm的玻璃珠，在壁面上不黏貼顆粒與黏貼1 mm、2 mm、2.5 mm、3 mm、5 mm的玻璃珠以提供粗糙因子0、0.5、1、1.25、1.5、2.5的實驗組數，旋轉速度為3、6、9、12 rpm皆在滾動流態下操作，加熱方式為以電熱加熱器環狀包覆旋轉鼓等熱通量加熱顆粒體，初始溫度為25 ，最終溫度為60 ，加熱過程中使用熱像儀進行旋轉鼓內顆粒體溫度場的拍攝，擷取溫度值後計算熱傳遞係數。運動行為分析上使用高速攝影機拍攝流場後以PIV進行速度場的計算，並以流動層面積比表示顆粒的混合能力。由研究結果指出，粗糙因子越高將降低接觸熱阻使熱傳遞係數越大，除了轉速的提升會增強粒子流的對流外，粗糙的壁面也會增強顆粒的混合能力提升熱傳遞係數。光滑的壁面與粗糙的壁面的熱傳遞係數與面積比呈現兩條線性的關係，初始的間距為接觸熱阻所造成。

The heat transfer coefficient between side wall and granular material in indirect heated rotating drum under different rotational speed and wall roughness was experimentally investigated in this study. The drum made by aluminum with inner diameter of 100 mm, thickness of 10 mm. Test particles are 2 mm glass beads. Smooth side wall and 1 mm, 2 mm, 2.5 mm, 3 mm, 5 mm glass beads be glued on side wall to provide six roughness factor: 0, 0.5, 1, 1.25, 1.5, 2.5. The drum be operated under rolling regime for rotational speed 3, 6, 9, 12 rpm. Drum be heated by electric heater apply constant heat flux from initial temperature 25 to final temperature is 60 . Obtain the temperature field by IR camera to calculate heat transfer coefficient. Analysis granular motion behavior by PIV to calculated velocity field. The area ratio is used to express the mixing ability of the particles. According to the results we find higher roughness factor will cause higher the heat transfer coefficient because thermal contact resistance decrease. Higher rotational speed will enhance granular convection and heat transfer coefficient. The heat transfer coefficient and area ratio of smooth wall and rough wall are expressed as two linear functions. The initial spacing is caused by the contact resistance.

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