This study analyses experimentally the heat transfer from the wall to the particle bed in a rotating drum with and without addition of built-ins for improving the mixing of the powder. Two types of materials were employed, sand as a granular material $\left(d_{\mathrm{p},\text{mean}}=200\mu \mathrm{m}\right)$ and cement raw meal as a powdery material $\left(d_{\mathrm{p},\text{mean}}=15\mu \mathrm{m}\right)$. A rotating cylinder heated through the outer shell was operated in batch mode, with rotational speeds of 1, 2 and 3 rpm and fillings of 5 and 10 %. The sand achieved a rolling motion, which makes the measured heat transfer coefficient predictable with theoretical models. At the contrary, cement raw meal showed very little mixing in a cylinder without built-ins and the measured heat transfer coefficient was much lower than the model predictions. Using longitudinal strips along the wall caused the powder to collapse regularly, increasing its heat transfer by a factor of 2–3, up to the range of predictions from theoretical models. Thus, a motion comparable to the rolling motion can be established with such built-ins which only cause limited dust formation. Furthermore, the limitations of the measurement method with rotating thermocouples are pointed out which mostly stem from the thermocouple response time and convectional losses, which are increased once built-ins are employed.

该研究通过实验分析了在旋转鼓中从壁到颗粒床的热传递，无论是否添加了用于改善粉末混合的内置插件。使用两种类型的材料，沙子作为颗粒材料$\left(d_{\mathrm{磷},\text{吝啬的}}=200\mu \mathrm{米}\right)$ 和水泥生料作为粉状材料 $\left(d_{\mathrm{磷},\text{吝啬的}}=15\mu \mathrm{米}\right)$. 通过外壳加热的旋转圆筒以分批模式运行，转速为 1、2 和 3 rpm，填充量为 5% 和 10%。沙子实现了滚动运动，这使得测量的传热系数可以通过理论模型进行预测。相反，水泥生料在没有内置装置的圆柱体中几乎没有混合，并且测量的传热系数远低于模型预测。沿壁使用纵向条带会导致粉末有规律地坍塌，将其传热增加 2-3 倍，达到理论模型的预测范围。因此，可以使用这种仅导致有限灰尘形成的内置装置来建立与滚动运动相当的运动。此外，