Useful checklist for airbag modeling:
  • All airbag fabric components are meshed with tria elements according to meshing requirements (3-4mm average size)
  • Airbag is free from intersections
  • If the airbag will be used in a larger simulation, the entity ID numbering is correct based on requirements of the larger model
  • The airbag model is divided into /SUBSET representing the airbag external surfaces, vents, internal surfaces, housing, and inflator
  • Mass and inertia of the model matches the physical part
  • Fabric material data was validated using biaxial, picture frame and uniaxial tests
  • Vent holes are modeled
  • Porous fabric is modeled
  • Gas material for each gas component is modeled
  • Inflator is validated using a tank test simulation and comparing the mass flow and temperature curves to the tank test results
  • Gas injections starts at TTF defined in /SENSOR Tdelay not by offsetting massflow and temperature curves
  • The mass flow curve start with non-zero values
  • C p ( T ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4qamaaBa aaleaacaWGWbaabeaakiaacIcacaWGubGaaiykaaaa@3A1B@ function is increasing monotonically for each gas
  • Reference geometry is present either as nodal based /XREF or element based /EREF
  • The same /SENSOR is used to activate injection and activate reference geometry in LAW58
  • Ambientand internal air material properties are specified
  • /FVMBAG1 card is specified
  • Internal airbag contacts defined and HyperCrash penetration check shows no intersections and a maximum penetration amount of 10% of the contact gap
  • Stability run is done to check for motion before TTF
  • Uniform pressure run is completed, no anchoring of contact nodes
  • Stand-alone FVM run is completed, no anchoring of contact nodes and realistic unfolding
  • Model runs with required time step
  • Number of FV does not reduce to one
  • Visual development of the flow (temperature contour plot, fluid velocity vector) is realistic
1 Clifford, M. J., A. C. Long, and P. Luca. "Forming of engineered prepregs and reinforced thermoplastics". The Minerals, Metals, and Materials Society (TMS) 2001 annual meeting, New Orleans. 2001.