(708g) Modifying the Johanson Roll Compaction Model for Improved Bulk Density Predictions

The Johanson’s (1965) roll compaction model is modified to improve predictions of the ribbon bulk density.  Previous FEM work has shown that the maximum pressure and ribbon bulk density predicted by the Johanson model are larger than those predicted from FEM simulations.  This over-prediction is due to the assumption of 1D flow in the Johansom model.  A mass correction factor is included in the Johanson model, similar to what was proposed by Bi et al. (2014).  In the present work, the mass correction factor and velocity profiles are presented based on FEM predictions.  In addition, an appropriate value of the mass correction factor is estimated from roll force measurements.   Using this modification, improved predictions of ribbon bulk density can be made.