1998 journal article
Pressure vs airflow characteristics through fresh intact and cut-strip tobacco
Transactions of the ASAE, 41(6), 1747–1753.
Pressure versus airflow characteristics were determined for various densities and cut sizes of green tobaccoleaves with leaf surfaces oriented either parallel or perpendicular to the airflow. The flowrate measurement deviceconsisted of a fan, PVC pipe, orifice plate, sealing apparatus, and a plenum. Graphs of pressure gradient versussuperficial velocity showed a nearly linear log-log relationship. Three equations were used to fit the data: the powerequation, ASAE standard equation, and Ergun equation. The Ergun equation provided the best fit in most cases. Analysisof variance of equation parameters with experiment variables showed that the pressure gradient was a function of the leafdensity squared. The only other factor affecting the pressure gradient was the leaf orientation. For a given velocity, leavesoriented perpendicular to the airflow had a pressure gradient about 10 times greater than that of the leaves orientedparallel to the airflow.