CODE Product Solutions

Transcription

1 CODE Product Solutions Simulation Innovations Glass Fiber Reinforced Structural Components for a Group 1 Child Harold van Aken

2 About Code Product Solutions Engineering service provider Specialised in Multiphysics Simulations Markets: Automotive Electronics Mechanical Engineering Consumer Goods. Off Shore Raw Material Production Excellent material knowledge for engineering plastics & metals and their production processes 1

3 Our way of working... Sustainable Business with our customers Bringing as much added value to the customer as possible (,Q,t) Think in solutions not in services Know the products & value chain of your customer Open communication Continuous improvement (investment in tools, training) Flexibility & Efficiency Our Solutions Optimisation of Products for cost, weight, manufacturing, assembly etc. Innovative product Design in combination with mechanical engineering Material advise on (engineering) plastics, metals, composites & hybrids CAE (Finite Element Analysis, Injection moulding simulations etc). 2

4 Our Tools Altair Hyperworks V9.0/V10.0 Pre- & post processing, Meshing Optistruct for geometrical optimisation Radioss for Crash, Impact, Drop, Fluid-Structure- Interaction, Acoustics, Multiphysics Autodesk Moldflow Advanced Code is the only Moldflow consulting partner in the Benelux with the complete package of simulation modules. From fill analysis, warpage analyses to electronic encapsulation and structural interface to Abaqus Simulia Abaqus V6.9 Implicit & Explicit simulations, Multiphysics In-house tool development But also: Material testing for Mechanical and/or rheological simulations Strain gauge, acceleration, temperature & displacement measurements 3

5 Description A modular seat concept for 1. Group 0+ (0-13kg) seats 2. Group 1 (9-18kg) seats Isofix car fixation system Electronic warning system for optimal safety 4

6 Project Goal of the project: 1. Replacing metal with plastics 2. Optimisation of plastic parts for: Crash performance (ECE & USNCAP for group 1 childseats) Total Cost of Ownership (Quality, production, assembly, etc.) 3. Reducing risks during development 4. No prototype tools for plastic parts 5

7 Development cycle 1. Simplified Explicit model of the complete seat Radioss 51 Elastic & elasto-plastic Material models Legal test with highest pulse (acceleration) 2. Shape Optimization of some parts Optistruct Use interface forces from previous explicit simulations elastic material models Optimize shape for stiffness & stability for given design space 3. Wall thickness optimization with large displacements Abaqus Standard Wall thickness optimization for optimized shape Optimize stresses & stability for large displacements 4. Glass fibre orientation prediction & weld lines Moldflow MPI Check fibre orientation for critical regions Optimize gating to avoid weld lines in critical regions 5. Explicit detailed model of the complete seat Radioss 51 Elastic & elasto-plastic Material models with strain rate dependency All Legal tests 6. Real life sled tests 6

8 The seat structure (2) 7

9 Simplified explicit model of the complete seat example: Lateral Beams Fy Fx V0 Vimposed Vimposed Initial Component velocity forces of complete are derived seat from structure interface according forcesto ECE or US-NCAP regulations Fixation In the example points, of car the seat lateral & car beam: floor deceleration Forces from shoulder according harness to ECE to or lateral US-NCAP beam pulse Pulse is translated into applied velocity profile vs. time (integration of deceleration-time curve) 8

10 Shape optimization Lateral beam Packaging Space Design Space for optistruct CAD model used to define packaging space and design space for topology optimization Optimization for compliance & buckling Optimization model includes injection moulding manufacturing constraints, like e.g. draw direction. Forces from simplified explicit simulations 9

11 Wall thickness optimization Example: Lateral beam New Wall thickness CAD design optimization is derived is from necessary optimized to: mid plane model compensate for translation from topology optimization to feasible design take into account large displacements, contact and material non linearity interference fit between cross tubes and lateral beam 10

12 Glass fibre orientation & weld lines Application Moldflow Orientation Structural Interface Integrative approach Abaqus Response During the development cycle several Moldflow calculations are used to: Check position of weld lines vs. high stressed area s Use fiber orientation prediction to evaluate allowable stresses A more integrate approach can be used by coupling Moldflow to Abaqus. Material properties from Moldflow fibre orientation prediction are used in the Abaqus structural calculations. 11

13 Optimization of the lateral beam Critical locations Location 5 Location 2 Location 4 Location 1 Isotropic, Allowable stress: +/-0.70*allowable datasheet stress Location 3 Location 6 Highly aligned, Allowable stress: +/-1.0*allowable datasheet stress 12

14 Results [USNCAP & ECE] Critical locations, 3D effects 3D geometry effects: All simulations on the complete seat have been carried out using an explicit (Radioss) solver, using shell elements for accuracy & efficient calculation time The drawback of shell elements is that Radii (3D geometry) cannot be represented Using solid elements with the required element density would yield long calculation times for the calculations. Therefore an implicit Abaqus model has been used to investigate the influence of 3D geometry effects. A reference model using the same mesh in shell elements in Abaqus is used a reference. The loads for this implicit model are derived from the explicit model. EXPLICIT MODEL IMPLICIT REFERENCE MODEL IMPLICIT (PARTLY) SOLID MODEL Belt Force: 1800N Belt Force: 2000N Belt Force: 2000N 13

15 Results [USNCAP & ECE] Critical locations, 3D effects EXPLICIT MODEL (Belt Force 1800N) IMPLICIT REFERENCE MODEL (Belt Force 2000N) IMPLICIT (PARTLY) SOLID MODEL (Belt Force 2000N) RED: Stresses>70Mpa!!! 14

16 Producing the product Left & right part out of one tool Two injection locations Sequential gate opening for optimal weld line positioning in critical area

17 Validation of the structural optimisation in Radioss 16

18 Summary In total 10 components / subsystems where optimised next to the lateral beam, using a combination of Radioss, Abaqus, Optistruct and Moldflow. All goals of the project where achieved: 1. Only 1 optimisation iteration nessecary after first test run. 2. no surprises project accomplished according to planning. 3. No prototype tools build. 4. Seat & base fullfull ECE & USNCAP requirements with plastic structural components Combining injection moulding simulations with mechanical simulations to design to the edge and to avoid classical mistakes like: Inproper weld line locations Glass fibre orientation for maximum strength & stiffness Excessive warpage of the parts 17

19 Thank you for your attention 18