Fiber Orientation Tensor Calculation for Injection Molding Accuracy

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for predicting the rate of change of fiber orientation in injection molding processes are inaccurate, particularly for parts with short flow lengths and fast filling speeds, resulting in overestimated fiber orientation rates.

Innovation Solution

A method that determines the rate of change of fiber orientation by calculating a first tensor for rigid body rotation and a second tensor for deformation, using a scalar value to reduce the deformation impact, and combining these to obtain an objective total rate of change tensor, which is more accurate than standard models.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a standard mathematical model is used to predict fiber orientation rate of change, then the model is simple to implement, but the prediction accuracy deteriorates significantly for parts with short flow lengths and fast filling speeds

Engineering Contradiction:
Improveprediction accuracy of fiber orientationVSAvoidcomplexity of calculation model
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the fiber orientation rate of change into two distinct components: a rigid body rotation component (W·A - A·W) and a deformation component (ξ(D·A + A·D - 2[α + (1-α)β]:D)). This segmentation allows each component to be calculated and adjusted independently, improving overall prediction accuracy by addressing the specific deficiencies of the standard model through targeted modifications to the deformation component.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a scalar reduction factor (where 0 ≤ ≤ 1) that modifies the deformation component of the fiber orientation rate of change. This parameter change allows the model to reduce the excessive deformation effects predicted by the standard model, particularly in scenarios with short flow lengths and fast filling speeds, thereby improving prediction accuracy without completely restructuring the mathematical framework.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If the standard model overestimates the rate of change of fiber orientation due to deformation, then calculation is straightforward, but the predicted fiber orientation does not match observed results

Engineering Contradiction:
Improveaccuracy of fiber orientation in molded partsVSAvoidreliability of prediction model
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The patent incorporates a feedback mechanism through the scalar reduction factor that adjusts the deformation component based on the specific flow conditions. By comparing the predicted orientation with expected physical behavior (particularly for short flow lengths and fast filling speeds), the model dynamically reduces the deformation contribution to achieve better agreement with observed fiber orientation, thereby improving both manufacturing precision and model reliability.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent modifies the deformation component by introducing a reduction factor that scales down the excessive deformation effects. This parameter change directly addresses the overestimation issue in the standard model, allowing the prediction to better match observed results while maintaining the overall structure of the mathematical model.

Inventive Principle:
Principle #35Parameter changes

3Measurement precision

If a scalar value is introduced to reduce deformation effects, then prediction accuracy improves, but the calculation complexity increases

Engineering Contradiction:
Improveaccuracy of fiber orientation predictionVSAvoidcomplexity of tensor calculation
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent introduces a single scalar reduction factor (where 0 ≤ ≤ 1) that modifies the deformation component of the fiber orientation rate of change. This simple parameter addition allows the model to correct prediction errors without requiring complex additional tensors or fundamental restructuring of the calculation framework, thus improving accuracy with minimal increase in computational complexity.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent applies the scalar reduction factor specifically to the deformation component (ξ(D·A + A·D - 2[α + (1-α)β]:D)) while leaving the rigid body rotation component (W·A - A·W) unchanged. This localized modification allows the model to improve accuracy in specific conditions (short flow lengths, fast filling speeds) without unnecessarily complicating the entire calculation system.

Inventive Principle:
Principle #3Local quality

Data Source

PatentUS7266469B1Method and article of manufacture for determining a rate of change of orientation of a plurality of fibers disposed in a fluid
Publication Date: 2007.09.04 APTIV TECHNOLOGIES AG
  • US7266469B1 patent drawing
  • US7266469B1 patent drawing
  • US7266469B1 patent drawing

AI summary

A method and an article of manufacture for determining a rate of change of orientation of a plurality of fibers disposed in a fluid are provided. The method includes determining a first tensor indicative of the rate of change of orientation of the plurality of fibers in the fluid in a predetermined region due to rigid body rotation of the plurality of fibers and the fluid. The method further includes determining a second tensor indicative of the rate of change or orientation of the plurality of fibers in the fluid in the predetermined region due to deformation of the plurality of fibers and the fluid in the predetermined region, utilizing a first scalar value that reduces the rate of change of orientation of the plurality of fibers due to deformation of the plurality of fibers and the fluid. The method further includes determining a third tensor indicative of a total rate of change of orientation of the plurality of fibers based on the first and second tensors, wherein the third tensor is an objective tensor.