Quantitative Definition of Liquid Irrigation Quality

Moore and Rukovena (289) developed an index for quantifying the quality of liquid irrigation to a packed column. This index is given by 

In order to determine Dq, each distributor drip point is represented by a circle. The center of the circle is located where the liquid from each drip point strikes the top of the bed. The area of each circle is proportional to the liquid flow, and the sum of all circle areas equals the tower cross-sectional area. If the liquid is evenly divided among all drip points, the area of each circle equals the tower cross-sectional area divided by the number of drip points. Terms A, B, and C in Eq. (3.1) are then evaluated as follows (Fig. 3.3a). 

A is the percent of the cross-sectional area at the top of the bed which is not covered by the drip point circles. This is a direct measure of the fraction of unirrigated area at the top of the bed. 

C is the total area of overlap of adjacent drip point circles expressed as a percent of tower cross-sectional area. 

A correlation (Fig. 3.26) proposed by Moore and Rukovena (289) can be used to determine the efficiency loss in a packed tower containing pall rings or Metal Intalox packing as a function of their distribution quality rating Dq and the number of stages in the bed. This correlation was only recently proposed, and more experience with its predic- 

---