Numerical shape development study in view of random packed beds – The Yo-Yo shape

A huge variety of shaped bodies geometries to be used in catalytic fixed bed reactors is available in industry. However, only sparsely shapes other than spheres, cylinders and hollow cylinders are systematically investigated by scientific institutions. As a starting point, the known geometries typically published in patents and patent applications are reviewed and classified regarding fabrication methods and shape characteristics. It is well known that even small variations of these shapes may have a major impact on fluid dynamics as well as in heat and/or mass transfer of the reaction system. An arbitrary selected Yo-Yo shape being a sphere with an equatorial duct of variable width, deepness and rounding radius is evaluated in regard to packing structure, flow field, pressure drop and residence time distribution. This study marks the first attempt to utilize the steadily increasing possibilities of numerical packing generation and computational fluid dynamics, for an in-deep understanding of shape impact and its potential for future automated shape optimization procedures.