针对管式固定床反应器内管束数量多、规模大等特点，选取单个管束作为特征结构。对装填不同直径柱状颗粒的管束，采用程序坐标定位的方法，建立柱状颗粒床层的物理模型。采用DEM与CFD联合数值仿真方法，探究反应管内径与柱状颗粒的等比表面积球当量直径之比(管径比Di/dp)对柱状颗粒床层流体流动的影响，并建立单管固定床反应器试验台，采用差压测试方法进行实验研究。结果表明，当Di/dp由5.37增至12.75时，床层空隙率和流体分布均匀性均得到改善，壁面效应的影响由床层中心减弱到管壁。基于数值模拟及实验结果对Di/dp=12.75的柱状颗粒床层进行床层压降Ergun公式常系数修正，CFD模拟计算的结果与拟合公式吻合较好。研究结果能为固定床反应器压降预测提供参考。

In view of the large number and large scale of tube bundles in the tubular fixed bed reactor, a single tube bundle was selected as the characteristic structure of the study. For the tube bundles filled with columnar particles of different diameters, the method of program coordinate positioning was adopted and the physical model of the columnar particle bed was established. DEM and CFD numerical simulation methods were used to explore the influence of the ratio of the inner diameter of the reaction tube to the equivalent surface area spherical equivalent diameter of columnar particles (Di/dp) on the fluid flow in the cylindrical particle bed. A single-tube fixed-bed reactor test device was established, and the differential pressure test method was used for experimental research. The results showed that when Di/dp increased from 5.37 to 12.75, the porosity of the bed and the uniformity of fluid distribution were improved, and the influence of the wall effect was weakened from the center of the bed to the tube wall. Based on the numerical simulation and experimental results, the bed pressure drop Ergun formula was corrected with constant coefficients for the columnar particle bed with Di/dp=12.75. The CFD simulation calculation results were in good agreement with the fitting formula. The research results provided guidance value for the design and application of fixed bed reactor.