Theoretical Estimates of the Porosity of Raschig Rings in the Wall Region of a Packed Column

A formula is derived for calculating porosity with an ordered installation of Raschig rings in the wall region of a packed column. Comparative calculations are made for the porosity in the wall region and the ordered arrangement of Raschig rings in rows inside the body of the apparatus specified in reference tables and determined using the theoretical formula. The effect the geometric dimensions (outer diameter and wall thickness) of Raschig rings, the inner diameter of the apparatus, and the number of freely installed rings have on the porosity in the wall area is demonstrated.