A finite-difference method for the prediction of velocity field in extrusion process

Ferretti, Gino; Montanari, Roberto

doi:10.1016/j.jfoodeng.2007.01.002

Cited by 5 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As an example, a finite difference scheme for the solution of the flow in a channel with finite aspect ratio was proposed in [ 75 ]. Results are in good agreement with the analytical solution proposed in [ 55 ], already for a coarse mesh.…”

Section: Models For the Materials Extrusionmentioning

confidence: 99%

“…Results are in good agreement with the analytical solution proposed in [ 55 ], already for a coarse mesh. The importance of the study presented in [ 75 ] is related to the possibility to perform analysis for non-rectangular cross-sections, such as that normally found in a single-screw extruder. This deviation from the ideal rectangular section is due to the fillets at the bottom of screw flights.…”

Section: Models For the Materials Extrusionmentioning

confidence: 99%

“…By performing numerical simulations, there is no longer the need to consider the correction factors for pressure and drag flows represented in Figure 11 or the shape factors introduced in [ 42 ]. The main drawback of [ 75 ] is to consider the isothermal flow of a Newtonian fluid.…”

Section: Models For the Materials Extrusionmentioning

confidence: 99%

See 2 more Smart Citations

Analytical and Numerical Models of Thermoplastics: A Review Aimed to Pellet Extrusion-Based Additive Manufacturing

2021

View full text Add to dashboard Cite

Recent developments in additive manufacturing have moved towards a new trend in material extrusion processes (ISO/ASTM 52910:2018), dealing with the direct extrusion of thermoplastic and composite material from pellets. This growing interest is driven by the reduction of costs, environmental impact, energy consumption, and the possibility to increase the range of printable materials. Pellet additive manufacturing (PAM) can cover the same applications as fused filament fabrication (FFF), and in addition, can lead to scale towards larger workspaces that cannot be covered by FFF, due to the limited diameters of standard filaments. In the first case, the process is known as micro- or mini-extrusion (MiE) in the literature, in the second case the expression big area additive manufacturing (BAAM) is very common. Several models are available in literature regarding filament extrusion, while there is a lack of modeling of the extrusion dynamics in PAM. Physical and chemical phenomena involved in PAM have high overlap with those characterizing injection molding (IM). Therefore, a systematic study of IM literature can lead to a selection of the most promising models for PAM, both for lower (MiE) and larger (BAAM) extruder dimensions. The models concerning the IM process have been reviewed with this aim: the extraction of information useful for the development of codes able to predict thermo-fluid dynamics performances of PAM extruders.

show abstract

Section: Models For the Materials Extrusionmentioning

confidence: 99%

Section: Models For the Materials Extrusionmentioning

confidence: 99%

See 1 more Smart Citation

Analytical and Numerical Models of Thermoplastics: A Review Aimed to Pellet Extrusion-Based Additive Manufacturing

2021

View full text Add to dashboard Cite

show abstract

“…The geometry of the extrusion die is an important parameter for the extrusion process, since it affects shear rate and residence time values of the extrusion metal, involving direct the outcome on the quality of the final product. Defects and flow instabilities are important limitations in processing operations for most materials, even in specialized extrusion processes such as screw extrusion of food products [2].…”

Section: Introductionmentioning

confidence: 99%

On the Velocity and the Strain Rate Field in Unlubricated Direct and Indirect Axisymmetric Extrusion of Al

Khorasani

Valberg

2014

KEM

View full text Add to dashboard Cite

The velocity and strain rate fields in the primary deformation zone ahead of the extrusion die opening are investigated by theory and FE-simulation for direct and indirect Al extrusion. The metal flow obtained in the FEM-models of extrusion is compared with the flow recorded in previous experiments and it is shown that the FE-analysis mimics real metal flow with good accuracy. The velocity and the strain rate fields computed by FEA (using DEFORM® 2D) are described and comparison is made with the idealized spherical velocity field of Avitzur, to see if there is good agreement between the results from theory and FEA, and the correlation between the results from the two is discussed. Moreover, a clear difference in metal flow is confirmed between the two processes direct (FwE) and indirect extrusion (BwE).

show abstract

“…The geometry of the extrusion die is an important parameter for the extrusion process, since it affects shear rate and residence time values of the extrusion metal, involving direct outcomes on the quality of the final product. Defects and flow instabilities are important limitations in processing operations of most extruded products [2].…”

Section: Introductionmentioning

confidence: 99%

Velocity Field in Direct, Indirect and Friction Assisted Extrusion of Al

Khorasani

Valberg

2013

KEM

View full text Add to dashboard Cite

This study investigates the velocity fields that are descriptive for the forward, backward and friction assisted extrusion of axisymmetric rods. The Avitzur theory was used to calculate the velocity field and strain rate in extrusion of Al alloys. Several simulations have also been performed by using finite element analysis (FEA) with DEFORM 2D, in order to find the admissible velocity field for different conditions of friction including high and low friction. The results from FEA and theory of axisymmetric extrusion are compared to see if there is good agreement. The correlation between the data obtained by theory and FEA is discussed.

show abstract

A finite-difference method for the prediction of velocity field in extrusion process

Cited by 5 publications

References 12 publications

Analytical and Numerical Models of Thermoplastics: A Review Aimed to Pellet Extrusion-Based Additive Manufacturing

Analytical and Numerical Models of Thermoplastics: A Review Aimed to Pellet Extrusion-Based Additive Manufacturing

On the Velocity and the Strain Rate Field in Unlubricated Direct and Indirect Axisymmetric Extrusion of Al

Velocity Field in Direct, Indirect and Friction Assisted Extrusion of Al

Contact Info

Product

Resources

About