Model and Numerical Simulation for the Second Penetration in Water-assisted Injection Molding
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S. Zhang
Abstract
Unlike gas-assisted injection molding, subsequent penetration occurs on the radial direction after water displacing polymer melt in cavity due to the incompressibility and fast cooling of water in water-assisted injection molding. To simulate this second penetration, a dimensionless method was employed to simplify the governing equations for melt flow. Based on the reduced model, a formula was derived via mathematical inference to calculate the second penetration velocity and distance. In order to catch the huge temperature gradient at water-polymer interface, both polymer and water thermal conduct problems were founded and coupled at the interface. The finite element method was employed to solve the melt flow problem, and the finite difference method was used to discretize the energy equation. To verify the validity of the proposed model and algorithm, experiments were performed to measure the displacement of the water–melt interface for various melt temperatures and water pressures. The experimental results indicate that the primary penetration theory is not accurately on predicting residual wall thickness, whereas the combined primary and second penetration method significantly improve the accuracy.
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© 2011, Carl Hanser Verlag, Munich
Articles in the same Issue
- Contents
- Contents
- Regular Contributed Articles
- Applicability of the Impact Response Analysis Method for Reinforced Concrete Beams Mixed with Polyvinyl Alcohol Short Fibers
- Epoxy-Montmorillonite Nanocomposites Applied to Powder Coatings
- Direct Imprinting Using Magnetic Nickel Mold and Electromagnetism Assisted Pressure for Replication of Microstructures
- Automated Mold Heating System Using High Frequency Induction with Feedback Temperature Control
- The Prediction of Bowing Distortion of Film after Transverse Stretching with Consideration of Heated Air Flow in a Tenter
- The Influence of Injection Molding and Injection Compression Molding on Ultra-high Molecular Weight Polyethylene Polymer Microfabrication
- A Design-of-Experiment Study on the Microcellular Extrusion of Sub-critical CO2 Saturated PLA Pellets
- Optimization of Injection Molding Process for SGF and PTFE Reinforced PC Composites Using Response Surface Methodology and Simulated Annealing Approach
- Flow Visualisation in Co-rotating Twin Screw Extruders: Positron Emission Particle Tracking and Numerical Particle Trajectories
- The Influence of Melt and Process Parameters on the Quality and Occurrence of Part Defects in Water-assisted Injection Molded Tubes
- Model and Numerical Simulation for the Second Penetration in Water-assisted Injection Molding
- Influence of Extrusion Conditions on the Rheological Behavior of Nuclear Bituminized Waste Products
- Influence of Dicumyl Peroxide Content on Thermal and Mechanical Properties of Polylactide
- Rapid Communications
- Calculation of Average Residence Time in a Ko-kneader
- PPS-News
- PPS News
Articles in the same Issue
- Contents
- Contents
- Regular Contributed Articles
- Applicability of the Impact Response Analysis Method for Reinforced Concrete Beams Mixed with Polyvinyl Alcohol Short Fibers
- Epoxy-Montmorillonite Nanocomposites Applied to Powder Coatings
- Direct Imprinting Using Magnetic Nickel Mold and Electromagnetism Assisted Pressure for Replication of Microstructures
- Automated Mold Heating System Using High Frequency Induction with Feedback Temperature Control
- The Prediction of Bowing Distortion of Film after Transverse Stretching with Consideration of Heated Air Flow in a Tenter
- The Influence of Injection Molding and Injection Compression Molding on Ultra-high Molecular Weight Polyethylene Polymer Microfabrication
- A Design-of-Experiment Study on the Microcellular Extrusion of Sub-critical CO2 Saturated PLA Pellets
- Optimization of Injection Molding Process for SGF and PTFE Reinforced PC Composites Using Response Surface Methodology and Simulated Annealing Approach
- Flow Visualisation in Co-rotating Twin Screw Extruders: Positron Emission Particle Tracking and Numerical Particle Trajectories
- The Influence of Melt and Process Parameters on the Quality and Occurrence of Part Defects in Water-assisted Injection Molded Tubes
- Model and Numerical Simulation for the Second Penetration in Water-assisted Injection Molding
- Influence of Extrusion Conditions on the Rheological Behavior of Nuclear Bituminized Waste Products
- Influence of Dicumyl Peroxide Content on Thermal and Mechanical Properties of Polylactide
- Rapid Communications
- Calculation of Average Residence Time in a Ko-kneader
- PPS-News
- PPS News
