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Rapid Numerical Estimation of Pressure Drop in Hot Runner System
Jae Sung Jung1, Sun Kyoung Kim1
1Department of Mechanical System Design Engineering, Seoul National University of Science and Technology, Seoul 01811, Korea.
Micromachines
|March 6, 2021
Summary
This study introduces a new computer tool to predict pressure drop in hot runner systems for plastic injection molding. This method offers a cost-effective alternative to expensive simulators for optimizing hot runner design.
Area of Science:
- Plastics Engineering
- Polymer Processing
- Computational Fluid Dynamics
Background:
- Accurate prediction of pressure drop in hot runner systems is crucial for effective plastic injection molding design.
- Current simulation software for pressure drop analysis is often costly and resource-intensive, limiting its use in routine design.
- Hot runner systems require precise dimensioning to manage material flow and prevent defects.
Purpose of the Study:
- To develop an accessible computer tool for calculating pressure drop in hot runner systems.
- To provide a cost-effective and efficient method for predicting pressure loss from sprue to gate.
- To aid designers in optimizing hot runner dimensions using a generalized Newtonian fluid model.
Main Methods:
- Development of a computational tool to simulate fluid flow.
- Application of a generalized Newtonian fluid model for steady flow conditions.
- Validation of the tool's accuracy against a commercial injection molding simulator for a four-drop system.
Main Results:
- The developed computer tool accurately calculates pressure drop in hot runner systems.
- The method provides reliable predictions comparable to commercial simulation software.
- The tool was successfully applied to a four-drop hot runner system, demonstrating its practical utility.
Conclusions:
- The proposed computer tool is a viable and accurate alternative for pressure drop prediction in hot runner design.
- This method simplifies the design process, making it more accessible for engineers.
- Optimizing hot runner dimensions through accurate pressure drop calculation enhances injection molding efficiency.
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