Pressure drop study on packings of differently shaped particles in milli-structured channels
Pressure drop study on packings of differently shaped particles in milli-structured channels
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DOI：
10.1016/j.ces.2016.08.011
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发表时间：
2016-11
影响因子：
4.7
通讯作者：
S. Hofmann;A. Bufe;G. Brenner;T. Turek
中科院分区：
文献类型：
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作者：
S. Hofmann;A. Bufe;G. Brenner;T. Turek
在狭缝宽度为1.5 - 3mm的毫米结构反应器中，对不同形状的颗粒填料（315-1000µm）进行了压降测量和计算。结果表明，当雷诺数在0.5<Reε<12范围内时，必须考虑d /比在6 ~ 14之间的填料的壁面效应，而层流占主导地位。尽管是针对圆柱形填料开发的，但先前提出的包括壁面效应在内的压降相关性也可以应用于狭缝型通道。对于非球形颗粒填料上压降的预测，建议用球度修正后的体积等效球直径来评价结果，而不是用索特直径。然而，只有当球度作为拟合参数时，才有可能精确地预测压降。此外，使用实际填料的微层析扫描来描述孔隙尺度下的几何形状，并使用晶格-玻尔兹曼方法进行流动和压降计算模拟。虽然在非球形催化剂颗粒的测量和模拟之间取得了很好的一致性，但模拟稍微高估了玻璃珠的压降。这些偏差很可能是由于扫描二值化过程中出现的伪影。
Pressure drop measurements and calculations were carried out for differently shaped packings of particles (315–1000 µm) in milli-structured reactors with slit widths of 1.5–3 mm. It could be shown that the wall effect in these packings withD/dratios between 6 and about 14 must be taken into account while laminar flow dominates for the employed Reynolds numbers in the range 0.5<Reε<12. Although developed for cylindrical packings, earlier proposed pressure drop correlations including wall effect terms can be also applied to slit-type channels. For prediction of pressure drops over packings of non-spherical particles it is recommended to evaluate the results with the volume-equivalent sphere diameter which is corrected by the sphericity instead of the Sauter diameter. An exact prediction of the pressure drop, however, is only possible if the sphericity is used as a fitting parameter. Furthermore µ-tomographic scans of real packings were used to describe the geometry for pore scale resolving simulations of the flow and pressure drop calculations using the lattice-Boltzmann method. While an excellent agreement between measurements and simulations was achieved for the non-spherical catalyst particles, the simulations slightly overestimated the pressure drop for the glass beads. These deviations are most probably due to artefacts occurring during the binarization procedure of the scans.