The Skelebrator Series Pipe Merging technique overcomes the basic drawbacks to series pipe removal that were mentioned previously in two ways:

First, the demand reallocation strategies normally available for this step are not comprehensive enough, limiting you to choosing from an even demand distribution or a distance-weighted one. This limitation can hinder your ability to maintain an acceptable level of hydraulic parity.

To overcome this limitation, Skelebrator provides a greater range of demand reallocation strategies, including: Equally Distributed, Proportional to Existing Load (at the ends of the new pipe), Proportional to Dominant Criteria, and User Defined Ratio. Evenly Distributed divides the demand equally between the two end nodes of the newly merged pipe. The Proportional to Existing Load divides demand based on the amount of demand already associated with the end nodes. The Proportional to Dominant Criteria strategy can supply the distance-weighted option and allows other pipe attributes to be weighting factors as well (for example, roughness or diameter). The User-Defined Ratio option assigns the specified proportion of demand to the upstream junction and the remainder of the demand to the downstream one. These additional choices allow the proper simulation of a wider range of hydraulic behaviors.

Second, and more importantly, this technique is effective because it allows you to specify tolerances that determine if the pipes to be merged are similar enough that combining them into a single pipe will not significantly impact the hydraulic behavior of the network. This increases the number of potential merge candidates over requiring exact matches, thereby increasing the scope of skeletonization but affecting hydraulics, since differences in hydraulic properties are ignored.

To counter the hydraulic effects of merging pipes with different hydraulic attributes, a unique hydraulic equivalency feature has been developed. This feature works by determining the combination of pipe attributes that will most closely mimic the hydraulic behavior of the pipes to be merged and applying these attributes to the newly merged pipe. By generating an equivalent pipe from two non-identical pipes, the number of possible removal candidates (and thus, the potential level of skeletonization) is greatly increased.

This hydraulic equivalency feature is integral to the application of a high degree of effective skeletonization, the goal of which is the removal of as many elements as possible without significantly impacting the accuracy of the model. Only Skelebrator implements this concept of hydraulic equivalency, breaking the barrier that is raised by other skeletonizers that only allow exactly matched pipes to be merged by this process.