Simulation Methods

FEM and Simulation of Manufacturing Processes

Simulation is a very import­ant step in the design, manu­fac­tur­ing and usage of compos­ite parts. For the produc­tion of compos­ites by resin infu­sion AAC can provide the inform­a­tion on the follow­ing aspects:

  • Draping simu­la­tion for the determ­in­a­tion of fiber orient­a­tion and sear­ing of the dry preform.
  • Infiltration simu­la­tion for the determ­in­a­tion of the process time, determ­in­a­tion of crit­ical loca­tion in the part like pores and dry spots, defin­i­tion of the best suited injec­tion strategy
  • Spring-In simu­la­tion – deform­a­tion of the part after demould­ing, redesign of the mold for the compens­a­tion of spring-in effects
  • Thermal simu­la­tion for the determ­in­a­tion of heat­ing– and cool­ing time, determ­in­a­tion of thermal gradi­ents, defin­i­tion of best suited heat­ing / cool­ing strategies
  • Mechanical simu­la­tion – determ­in­a­tion of deform­a­tions due to injec­tion pres­sure, design of mold­ing concepts

Beside process relev­ant simu­la­tion, AAC provide stand­ard thermal, struc­tural and multi-phys­ical FE simu­la­tions includ­ing struc­tural beha­vior of compos­ite and hybrid compos­ite – metal struc­tures using differ­ent state of the art fail­ure models for first ply fail­ure and progress­ive damage. simulation methods_1The follow­ing simu­la­tion tools are avail­able at AAC:

ANSYS – Multiphysics / ACP

FEM simu­la­tion, thermal and mech­an­ical (static, dynamic) beha­vior ACP: ANSYS Composite Pre-Post Analysis

PAM-RTM

RTM: clas­sical isothermal closed mold resin trans­fer mold­ing. VARI: Vacuum Assisted Resin Infusion. Isothermal injec­tion under deform­able plastic film. The thick­ness and permeab­il­ity change of the fiber rein­force­ment is taken into account. Heated RTM: non-isothermal RTM. Heat exchanges between resin, fiber rein­force­ment and mold is taken into account. The effect of resin poly­mer­iz­a­tion on viscos­ity and heat gener­a­tion can also be taken into account. Preheating: heat­ing of the mold and fiber rein­force­ment before filling. The possibly non-uniform temper­at­ure distri­bu­tion at the end of preheat­ing can be used to initial­ize Heated RTM simu­la­tion. Curing: post-filling resin cure. By default, assumes that the cavity is completely filled and the initial temper­at­ure and degree of cure is uniform. Otherwise the results of the Heated RTM simu­la­tion (filling factor, temper­at­ure, degree of cure) can be used to initial­ize the curing simu­la­tion. Pre-simu­la­tion: this simu­la­tion allows a first approx­im­a­tion of the filling time and flow. QUIK-FORM: drap­ing analysis of fiber rein­force­ments (bi-direc­tional fabrics and unidirec­tional). Alfalam: Laminate theory, MS Excel, [ABD] matrix, Puck fail­ure criteria eLamX: Laminate theory, Java, [ABD] matrix, 3D fail­ure envel­ope plots tu-dresden.de LamiCens: Laminate theory, MS Excel, [A] Matrix, Graphics www.r-g.de Texgen: Generation of texture TexGen is open source soft­ware licensed under the General Public License developed at the University of Nottingham for model­ling the geometry of textile struc­tures. MyRTM: myRTM is an easy-to-use program for simu­lat­ing the mould-filling phase of the Resin Transfer Molding (RTM) process. iwk.hsr.ch CADEC: Computer Aided Design Environment for Composites, Laminate theory, [ABDH] matrix, FEM applic­a­tion www.mae.wvu.edu

Mathematical simulation

Maxima: Computer algebra system, matrix manip­u­la­tion, manip­u­la­tion of symbolic and numer­ical expres­sions, differ­en­ti­ation, integ­ra­tion, Taylor series, Laplace trans­forms, ordin­ary differ­en­tial equa­tions, systems of linear equa­tions, poly­no­mi­als. maxima.sourceforge.net Scilab: Maths & Simulation, 2-D & 3-D Visualization, Optimization, Statistics, Control System Design & Analysis, Signal Processing, Application Development, Xcos (hybrid dynamic systems modeler and simu­lator) fully integ­rated www.scilab.org Gnuplot: port­able command-line driven graph­ing util­ity