Student Research: Ted F. Carrell

MS, , 1993
Faculty Advisor:

Validation of Power Loss Modeling in Predicting the Effects of Removing One or More Branches from a Five Branch Ventilation System


Ventilation systems are critically important in protecting workers from airborne contaminants. Given the long life spans of ventilation systems and constantly changing processes they serve, the ability to re-design existing systems to correct problems or meet new requirements is crucial to the continued protection of worker health. However, few mathematical tools and procedures exist to guide engineers and industrial hygienists in redesigning systems to meet new requirements. Power loss modeling was developed by Guffey in 1989 to provide such a tool.

The main objective of this study was to determine if the power loss model could be used to accurately predict and characterize flows and pressures in a full scale ventilation system after deleting branches from the system.

A full scale, five branch venilation system was characterized and power losses determined for each of the junctions. The power loss coefficients were used to predict the ffect of removing branches on the airflow through each of the remaining branches. The subject branch was then removed and the remaining system characterized based on measured values. Six configurations were tested in the experimental system. The percent error in predicted airflows versus measured airflows varied from 0.04 to 6.03.