A CFD model with free surface tracking: predicting fill level and residence time in a starve-fed single-screw extruder

Modeling Residence Time Distribution in a Twin-Screw Extruder as a Series of Ideal Steady-State Flow Reactors

Knowledge about and control of residence time distribution (RTD) is critical for determining optimal conditions in an extrusion process. In this paper, previously proposed models for RTD have been summarized and compared with the experimental data. The best-fit model was found to be a plug flow in series with a finite number of constantly stirred tank reactors having dead volume fractions. Para...

Continuous Granulation with a Twin-Screw Extruder

Entropy Time Evolution in a Twin Flight Single Screw Extruder and its Relationship to Chaos

The flow fields in polymer processing exhibit complex behavior with chaotic characteristics, due in part to the non-linearity of the field equations describing them. In chaotic flows fluid elements are highly sensitive to their initial positions and velocities. A fundamental understanding of such characteristics is essential for optimization and design of equipment used for distributive mixing....

A single-vendor and a single-buyer integrated inventory model with ordering cost reduction dependent on lead time

Lead time is one of the major limits that affect planning at every stage of the supply chain system. In this paper, we study a continuous review inventory model. This paper investigates the ordering cost reductions are dependent on lead time. This study addressed two-echelon supply chain problem consisting of a single vendor and a single buyer. The main contribution of this study is that the in...

Design of a Feedback Control System for Real-time Control of Flow in a Single-screw Extruder

A closed loop controller is designed for regulation of the volumetric output flow in a polymer extruder. To this aim, temperature and pressure at the machine output must be controlled on the basis of real time measurements. It has been verified that temperature and pressure regulations can be achieved by solving two disjoint control problems. The temperature controller acts on the heat delivere...