Capabilities and Limitations

AMS is compatible with the following options:

Kinematic Conditions

  • Boundary conditions: /BCS
  • Imposed velocities: /IMPVEL
  • Imposed displacements: /IMPDISP
  • Imposed accelerations: /IMPACC
  • Tied contacts: /INTER/TYPE2 Spotflag 0, 1, 2 (kinematic formulation), 25, 27 or 28 (penalty formulation)
    • Rigid bodies: /RBODY (provided they are not sensor activated or deactivated)
    • Fixed rigid walls: /RWALL with node_ID= 0 or blank (in case of friction, it is still advised to use a rigid meshed impactor, due to AMS cost)
    • Moving rigid walls: /RWALL with node_ID > 0 (in case of friction, it is still advised to use a rigid meshed impactor, due to AMS cost)
    • Rigid links: /RLINK
    • Kinematic joints: /KJOINT (/PROP/TYPE33) and /KJOINT2 (/PROP/TYPE45)
    • Cylindrical joints: /CYL_JOINT
    • Active sections: /SECT
    • Velocities: /VEL/TRA or /VEL/ROT
    • Initial velocities: /INIV/TRA or /INIV/ROT
  • Rigid bodies can be activated and deactivated with /RBODY/ON and OFF as Engine keywords
  • Rigid elements: /RBE2
  • Interpolation constraint elements: /RBE3

Elements

  • All classical: trusses, beams, springs, shells, and solids
  • 4-node tetra: /TETRA4, only if Itetra4=0
  • 10-node tetra: /TETRA10, only if Itetra10=0
  • Element formulation:
    • QEPH Ishell=24 and all other Ishell options
    • HEPH Isolid=24

Interfaces

/DT/AMS is compatible with interfaces.
  • TYPE2 (see Tied contacts above)
  • TYPE7
  • TYPE10
  • TYPE11
  • TYPE19
  • TYPE21
  • TYPE24
  • TYPE25
  • Dynamic relaxation: /DYREL, /ADYREL
  • Rayleigh damping: /DAMP
  • /DT/Eltyp/Keyword3 is compatible with /DT/AMS
    This includes /DT/Eltyp/CST for which the small strain formulation is activated for an element when(1)
    Δ T s c a ⋅ l c < Δ T min MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaacaqGuoGaam ivamaaBaaaleaacaWGZbGaam4yaiaadggaaeqaaOGaeyyXIC9aaSaa aeaacaWGSbaabaGaam4yaaaacqGH8aapcaqGuoGaamivamaaBaaale aaciGGTbGaaiyAaiaac6gaaeqaaaaa@4575@
    Where,
    l MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaacaWGSbaaaa@374F@
    Element characteristic length,
    c MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaacaWGJbaaaa@3746@
    Speed of sound into the material
  • /DT/AMS applied to selected parts (in /AMS from Starter Input file) does not exclude concurrent usage of /DT/NODA/CST applied to non-AMS designated parts of the rest of the model. This is even advised in order to minimize computing time in models where AMS only applies to selected parts.
    Note: It is pointless to use a higher time step in AMS than the one used in classic mass scaling since the smaller time step limits the performance.
  • Airbags without reference metrics should work