LS-DYNA R10.0.0 (R10.118302) released

New version of LS-DYNA is released for all common platforms.

Release notes for LS-DYNA R10.0.0

Herein are summarized new features and enhancements in version 10.0.0.  Some bug fixes are also described, some of which may also be included in R9 releases.

The items are arranged by category.  Understand that in many cases, a particular item could fall under more than one category, but in the interest of brevity, each item is listed only once, under a single category.

Excluding the “Miscellaneous” category, the categories are arranged alphabetically.

CESE (Compressible Fluid Solver)
  • The absolute tolerance argument is no longer used by the BV solver. As an example, the following is all that is needed for CESE moving mesh problems:
  • *CESE_CONTROL_MESH_MOV  $     ialg   numiter    reltol           1       500    1.0e-4
  • Also corrected the CESE moving mesh solvers for a special case involving a wedge element. Also, fixed the d3plot output of wedge element connectivities for the CESE moving mesh solvers.
  • In conjunction with the above, new FSI and conjugate heat transfer output on solid (volume) mesh outside boundaries is now supported.
    *CHEMISTRY CONTROL_INFLATOR, $  isolver   ioutput   runtime      delt    p_time          1         0       0.1    1.0e-6    5.0e-4 with "isolver set to 1", the user can simulate a conventional Pyrotechnic inflator mode, while with "isolver" set to 2 or 3, Hybrid inflator simulation is possible.
    isolver = 2 => Hybrid model for the cold flow isolver = 3 => Hybrid model for the heated flow.
    $card1: propellants $  comp_id     p_dia  p_height    p_mass   p_tmass         10     0.003    0.0013    2.0e-5  5.425e-3 $card2: control parameters $  t_flame    pindex        A0     trise    rconst      2473.       0.4   4.45e-5       0.0     0.037 - In the first card, the user can specifiy the total amount of propellant particles and their shape. - Using the second card, the user can also specifiy the thermodynamics of the propellant and its burning rate.    To support the options in card2, especially the second option, pindex, and the third, A0,    we provide a standalone program upon request for the propellant equilibrium simulation.    The remaining cards are for the combustion chamber, gas chamber, and airbag, respectively.
    Discrete Element Method (DEM)
    Magnee, A., Generalized law of erosion: application to various alloys and intermetallics, Wear, Vol. 181, 500, 1995.
  • Modify tangential force calculation to get better rigid body rotation behavior for *DEFINE_DE_BOND
  • Support restart feature for DEM interface force file and *DATABASE output.
  • Instead of using bulk modulus, use mass and time step to estimate contact stiffness for SPH-DEM coupling. This should be better if DEM material is quite different from SPH material.
  • Fix *DEFINE_DE_MASSFLOW_PLANE bug if DE injection is defined.
  • Add CID_RCF to *DEFINE_DE_TO_SURFACE_COUPLING for force output in local coordinates to ‘demrcf’ file.
  • Update the *DEFINE_DE_BY_PART card so that it matches the capabilities of the *CONTROL_DISCRETE_ELEMENT card.
  • Add penalty stiffness scale factor, thickness scale factor, birth time and death time to *DEFINE_DE_TO_SURFACE_COUPLING.
  • Add dynamic coefficient of friction to *CONTROL_DISCRETE_ELEMENT.
  • Implement Finnie’s wear law and user defined wear model to *DEFINE_DE_TO_SURFACE_COUPLING.
  • Implement user-defined curve for DEM frictional coefficient as function of time.
  • Implement user-defined curve for contact force calculation for *CONTROL_DISCRETE_ELEMENT.
  • Fix inconsistent results between *DEFINE_DE_BY_PART and *CONTROL_DISCRETE_ELEMENT.
    1. if IST on *SECTION_BEAM is non-zero, the output forces and moments are supposed to be rotated into the beam’s principal axis system, but this rotation could be applied to the wrong beam elements; and
    2. when no ELFORM=2 elements have IST, but the model also contains beams with ELFORM=6 and RRCON=1 on the *SECTION_BEAM card, some of the ELFORM=2 elements can have their output forces and moments rotated by 1 radian.
    1. velocity is prescribed on the rigid body that the accelerometer is attached to, and
    Electromagnetic Solver (EM)
    D3PL_RAND_r0_EM,  D3PL_RAND_r10_EM,  D3PL_RAND_c10_EM,  D3PL_RAND_soc_EM,  D3PL_RAND_i_EM,  D3PL_RAND_u_EM,  D3PL_RAND_v_EM,  D3PL_RAND_vc_EM,  D3PL_RAND_temperature_EM,  D3PL_RAND_P_JHR_EM,  D3PL_RAND_P_dudt_EM,  D3PL_RAND_i_vector_EM This output can be visualized in LS-PrePost versions 4.3 and 4.5 on the separator part of the battery cell using Post/FriComp/Extend/EM node.
  • Added tshells for EM analysis for use in battery modeling.
  • Added new capability for modeling Randles short, based on *DEFINE_FUNCTION so that the user has a lot of freedom to define where and when the short happens as well as the short resistance.
  • Added a new capability for battery exothermal reactions also based on *DEFINE_FUNCTION. The new keyword *RANDLE_EXOTHERMAL_REACTION makes it possible to complement the heating of a short circuit created by a short by exothermal reactions if, for example, the temperature becomes higher than a threshold value.
  • Forming Analysis
    VAD1 = 5: enforced velocity by large mass method      = 6: enforced acceleration by large mass method      = 7: enforced displacement by large mass method      = 8: torque      = 9: base angular velocity      =10: base angular acceleration      =11: base angular displacement
  • Added rotational dof output for FRF.
  • VAD =5: enforced velocity by large mass method     =6: enforced acceleration by large mass method     =7: enforced displacement by large mass method     =8: torque
  • Fix for running SSD fatigue in MPP (affected keyword: *FREQUENCY_DOMAIN_SSD_FATIGUE).
  • Updated ssd computation with local damping, and enabled the restart feature by reading damping matrix.
  • Implemented ERP (Equivalent Radiated Power, keyword *FREQUENCY_DOMAIN_SSD_ERP) for MPP.
  • *DATABASE_FREQUENCY_ASCII: Added keyword *DATABASE_FREQUENCY_ASCII_{OPTION} to define the frequency range for writing frequency domain ASCII databases NODOUT_SSD, ELOUT_SSD, NODOUT_PSD and ELOUT_PSD.
  • Incompressible Fluid Solver (ICFD)
    Implicit (Mechanical) Solver
    Isogeometric Elements
    *MAT and *EOS
    1. The number of potential cracks in *MAT_197 shell elements has been increased from 2 to 4. *MAT_197 uses a fixed crack model: once the first crack forms, it remains at the same fixed angle relative to the element axes. Further cracks can then form only at pre-defined angles to the first crack. Previously, only one further crack could form, at 90 degrees to the first crack. Thus, if the loading direction subsequently changed so that the principal tension is at 45 degrees to the first crack, that stress could exceed the user-defined tensile strength by a considerable margin. Now, further cracks may form at 90, +45 and -45 degrees to the first crack. Although the maximum principal stress can still exceed the user-defined tensile strength, the “error” is much reduced. There is an option to revert to the 2-crack model as in R9 (to do this, add 100 to TYPEC).
    2. Add element erosion to *MAT_197. This change may lead to different results compared to previous versions, because erosion strain limits are now added by default. Elements are now deleted when crack-opening strain becomes very large, or the material is crushed beyond the spalling limit. Plastic strain in the rebar is considered too. Previously, these elements that have passed the point of being able to generate any stress to resist further deformation would remain in the calculation, and sometimes showed very large non-physical deformations and could even cause error terminations. Such elements would now be deleted automatically. Default values are present for the erosion strains but these can be overridden in the input data, see new input fields ERODET, ERODEC, ERODER.
    3. New history variables 10,11,12 (maximum value so far of through-thickness shear stress). This is useful for checking results because *MAT_197 cracks only in response to in-plane stress; before cracking occurs, the through-thickness shear capacity is unlimited. The data components are:
      Ex History Variable 10 - maximum out of 11 and 12 Ex History Variable 11 - maximum absolute value of YZ shear stress Ex History Variable 12 - maximum absolute value of ZX shear stress These are in the element local axis system. Note that these variables are written only if TYPESC is zero or omitted. TYPESC is a pre-existing capability that requests a different type of shear check.
    4. Fixed bug. Elastic stiffness for *MAT_197 beams was not as described in the manual, and the axial response could sometimes become unstable. The bug did not affect shell elements, only beams.
    5. *MAT_197 can now handle models with temperatures defined in Kelvin (necessary if the model also has heat transfer by radiation). *MAT_197 has thermally-sensitive material properties hard-wired to assume temperatures in Centigrade. A new input TMPOFF in *MAT_197 offsets the model temperatures before calculating the material properties.
    6. When the input parameter AGGSZ is defined, the maximum shear stress that can be transferred across closed cracks is calculated from a formula that has tensile strength and compressive stress as inputs. In *MAT_197, the tensile strength of concrete is reduced when compressive damage has occurred (see description of UNLFAC). Up to now, compressive damage was therefore influencing the maximum shear across cracks. However, the Norwegian standard from which the shear forumla is taken treats the tensile strength as a constant. Therefore, for the purpose of calculating the maximum shear stress across closed cracks only, the compressive damage effect is now ignored.
    7. Added capability for water pressure in cracks, for offshore applications. The water pressure is calculated from the depth of the element below the water surface (calculated from the z-coordinate). The water pressure is applied as a compressive stress perpendicular to the plane of any crack in the element. See new input fields WRO_G and ZSURF.
    $      ef0      plim         q      gama         m       0.70     925.7     0.970     0.296      2.04 
    decomp { region { partset 12 local c2r 30 0 -30 0 1 0 1 0 0 } }
  • would apply the c2r transformation in the coordinate system of the include file, which wasn’t previously possible. The local option can be useful even if there are no such transformations, as the “cubes” that the decomposition uses will be oriented in the coordinate system of the include file, not the global system.
  • Furthermore, the following decomposition related keywords now have a _LOCAL option, which has the same effect:
    Output control flags: 0-no 1-yes IGLB : Global data IXYZ : Current coordinate IVEL : Velocity IACC : Acceleration ISTRS: 6 stress data + plastic strain ISTRA: 6 strain data ISED : Strain energy density
  • This command can be used in combination with regular *DATABASE_EXTENT_BINARY but will disable most of the options in the latter, including output of extra history variables.
  • Restarts
    SPG (Smooth Particle Galerkin)
    SPH (Smooth Particle Hydrodynamics)
    Thermal Solver