(788f) Two-Phase Flow (solids: interstitial air) Modeling of a Press Feed System
- Conference: AIChE Annual Meeting
- Year: 2016
- Proceeding: 2016 AIChE Annual Meeting
- Group: Pharmaceutical Discovery, Development and Manufacturing Forum
- Time: Friday, November 18, 2016 - 4:55pm-5:15pm
Two-phase flow risks can be accounted for during process design by:
- Measuring key flow properties to use as inputs in the two-phase flow model;
- Computational modeling the two-phase flow effects based upon first principle models;
- Evaluating potential corrective actions through two-phase modeling.
The two-phase modeling software uses key powder flow properties, including:
- Specific gravity of a particle
- Wall friction angles (phi-prime, fâ??)
- Effective angle of internal friction (delta, d) measured via a cohesive strength test.
The two-phase model as includes the press feed system geometry and process parameters as inputs. The model outputs include parameters that dictate two-phase flow behavior, such as vertical solids stress, interstitial gas pressure, bulk density and normalized gas pressure gradient. These modeling outputs are used to predict whether flow problems will occur and analyze potential corrective actions, including modifying the geometry of the press feed system, increasing the permeability of the powder and adding venting.