CONTRIBUTION TO BMW i.

Transcription

1 Markus Dix, LCC 5th Anniversary Symposium CONTRIBUTION TO BMW i. INCREASED FRONTLOADING OF AUTOMOTIVE CFRP DEVELOPMENT TASKS USING EXTENDED VIRTUAL PROCESS CHAINS.

2 AGENDA. 1. Motivation 2. Problem description 3. Solutions with simulation methods 4. Enhanced simulation models 5. Validation and qualification 6. Examples BMW i 7. Summary and outlook LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 3

3 MOTIVATION. BMW i3 BMW i8 LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 5

4 PROBLEM DESCRIPTION. RTM PROCESS CHAIN. Examples of interrelationships inbetween sequential process steps Overlapping areas Ability for injection Dimensional stability Faser- Fiber herstellung production Gelege- Textile manufacturing herstellung Stacking Stackprocess prozess Preformen &. Preforming & Preform- Cutting schneiden Konfektionieren (Verbinden Assembly der Preformlinge) RTM Vacuum Injection Endbeschnitt Trimming (Wasserstrahl- (water jet schneiden) cutting) Corundum Korundblasting strahlen Nur Großbauteile Fiber quality Drapability Ability for injection Targets: Design of machines, tools and processes LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 7

5 SIMULATION METHODS. OVERVIEW OVER RTM PROCESS CHAIN. Iteration loops feasability for manufacturing Current design of Preforming Tool Current design of RTM Tool Warpage compensation Draping simulation Filling simulation Warpage simulation LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 9

6 SIMULATION METHODS. DRAPING SIMULATION. Fiber orientation (UD 0 layer) Information from multiple layers Shear angle (UD 0 layer) LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 10

7 SIMULATION METHODS. FILLING SIMULATION. Injection concept Degree of filling = f(t) Filling time [s] LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 12

8 SIMULATION METHODS. WARPAGE SIMULATION. Material model according to CLT Composite Solid elements used Simulation and validation on real part geometry Principle model Spring-In LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 14

9 PROBLEM DESCRIPTION. SIMULATION ENVIRONMENT DEMANDS. Iteration loops feasability for manufacturing Current design of Preforming Tool Current design of RTM Tool Warpage compensation Draping simulation Filling simulation Warpage simulation Tool B Tool A Tool C Tool D Tool E Tool F Interface Crash simulation Iteration loops part development and performance 1) Development platform 2) Operative usage LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 16

10 Industrial applications ENHANCED SIMULATION MODELS. STATE OF THE ART. Metal casting Audi [1] Sheet metal forming Daimler [2] RTM process simulation [3] 2004: Louis, Zur Simulation der Prozesskette von Harzinjektionsver fahren (IVW, Kaiserslautern) [6] No solution on the market can fully link single simulation steps regards all phenomena occurring in RTM process reality Injection molding technology Composite process simulation FAT [4] DLR [5] Research & Development LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 17

11 ENHANCED SIMULATION MODELS. INTERFACE CONCEPT. Draping simulation fiber volume fraction part geometry Warpage simulation Numerical modules Interface Phenomenological material modules fiber orientation fiber volume fraction part geometry Filling simulation filling time Classical simulation approach of sequential process steps [6] Additional interface and modular interface operations Modular interface operations LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 18

12 PRINCIPLE PART 4XL-PROFILE. DRAPING AND RTM EXPERIMENTS. Preforming Injection Diaphragma forming Industrialized experimental device Material influence of industrial forming Data aquisition Defined forming effects close to real part geometries Capability to do experiments without press Capability to do experiments with universal testing machine (Zwick) to measure closing force Experiments on warpage of CFRP parts Experiments on thickness and fiber volume fraction Flow front experiments, visualization, CFRP parts Principle part for entire experimental process chain Virtuelle CFK-Prozesskette, Markus Dix, MT-121, Juni 2014 Seite 20

13 EXAMPLES BMW i. STRUCTURAL PARTS 1. Process simulation in early development phases for BMW i3 with local material properties Visualization of part warpage (factor 20) of a floor panel (BMW i3) Filling simulation of a side frame structure (BMW i3) LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 24

14 EXAMPLES BMW i. VIRTUAL PROCESS CHAIN. Draping simulation Preform thicknes Solver Interface parameters: Layup Overall preform thickness Fiber volume fraction Permeability (2D) Fiber orientation (per layer) Material properties for target simulation Permeability K1/K2 Interface Filling simulation Warpage simulation Solver Solver Fiber direction LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 25

15 SUMMARY. Manufacturing processes for CFRP automobile parts (e.g. RTM) are in most cases complex ones (material, process design, ). The BMW Group makes use of process simulation intensively for CFRP product and process development (draping, filling, warpage). A modular interface with full coupling of all RTM process steps has shown better simulation accuracy and faster modeling tasks. Capabilities from commercial CAE software (e.g. ANSA) can cover most of the numerical requirements for such an interface. Automation of mapping, calculation and data exchange is a key factor, which can be addressed by scripting functionalities. Process simulation contributes greatly to process robustness and quality. LCC 5th Anniversary Symposium, Markus Dix, 11 th Sept Page 28

16 THANK YOU FOR YOUR ATTENTION! QUESTIONS?