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<div><p>Dear all,</p><p>I have identified several sub‑keyword classes in<br>...\Lib\site-packages\ansys\dyna\core\keywords\keyword_classes\auto<br>that are incorrectly implemented in the pydyna 0.11.0 release.</p><p>Examples include:</p>define_curve.pydefine_table.pydefine_transformation.pyinitial_strain_solid.pyinitial_stress_solid.pyparameter.pyset_node_general.py...and others.<p>The main issues are related to incorrect data structures, particularly in implementations intended to support multi‑line inputs using a generic Card, whereas the proper data structures should be SeriesCard, TableCard, or TableCardGroup.</p><p>In addition, several other problems have been identified. For example, the INITIAL keyword family is located in the wrong place within the library (inside the boundary directory), while the initial directory is missing entirely.</p><p>I would appreciate hearing from others who may be dealing with similar issues.</p></div>

<p>Goodmorning,</p><p>I'm analysing the impact of a BEAM element with MAT_ELASTIC on the water. </p><p>I need the local pression in different points of the body. I've definied with DATABASE_FSI several different points but importing the .dbfsi results file in post processing I get the same plot for all the points. </p><p></p><p>The odd points I've defined don't plot any results, just a straight line at 0. </p><p>What I'm doing wrong? Is there another keyword to define?</p>

<p>After compiling the umat code and using it, the mesh deformation is not visible in the post processing. this is the code which I replaced in the subroutine umat 41. It is just not showing the deformation but there is change in the resultant velocity at nodes. What may the reason and how to fix this.</p><p> subroutine umat41 (cm,eps,sig,epsp,hsv,dt1,capa,etype,tt,<br>     & temper,failel,cma,qmat,elsiz,idele,reject)</p><p>      include 'nlqparm'<br>      include 'bk06.inc'<br>      include 'iounits.inc'</p><p>      dimension cm(*),eps(*),sig(*),hsv(*),cma(*),qmat(3,3)<br>      logical failel,reject<br>      character*5 etype<br>      integer*8 idele</p><p>c ===============================<br>c LOCAL VARIABLES<br>c ===============================</p><p>      real*8 Kmod,Gmod,sig_t,phi,coh,alpha,beta<br>      real*8 Kmod_d,Gmod_d<br>      real*8 eps_v,eps_cr,Cd,D<br>      real*8 e1,e2,e3<br>      real*8 I1,J2,s1,s2,s3<br>      real*8 phi_r,dp_a,dp_k,f,scale<br>      real*8 tiny</p><p>      tiny = 1.0d-20</p><p>c ===============================<br>c MATERIAL PARAMETERS FROM CARD<br>c ===============================</p><p>      Kmod  = cm(1)<br>      Gmod  = cm(2)<br>      sig_t = cm(3)<br>      phi   = cm(4)<br>      coh   = cm(5)<br>      alpha = cm(6)<br>      beta  = cm(7)</p><p>c ===============================<br>c ONLY FOR SOLID TYPE ELEMENTS<br>c ===============================</p><p>      if (etype.eq.'solid'.or.etype.eq.'sph  '.or.<br>     &    etype.eq.'sldax'.or.etype.eq.'sld2d') then</p><p>      if (.not.failel) then</p><p>c ===============================<br>c VOLUMETRIC STRAIN<br>c ===============================</p><p>      eps_v = eps(1)+eps(2)+eps(3)</p><p>c ===============================<br>c CRITICAL TENSILE STRAIN<br>c (using bulk modulus relation)<br>c ===============================</p><p>      eps_cr = sig_t/(3.d0*Kmod + tiny)</p><p>c ===============================<br>c DAMAGE EVOLUTION<br>c ===============================</p><p>      if (eps_v.gt.eps_cr) then<br>         Cd = alpha*(eps_v-eps_cr)**beta<br>      else<br>         Cd = 0.d0<br>      endif</p><p>      D = 1.d0 - dexp(-Cd)</p><p>c ===============================<br>c DEGRADED STIFFNESS<br>c ===============================</p><p>      Kmod_d = (1.d0-D)*Kmod<br>      Gmod_d = (1.d0-D)*Gmod</p><p>c ===============================<br>c DEVIATORIC STRAIN<br>c ===============================</p><p>      e1 = eps(1)-eps_v/3.d0<br>      e2 = eps(2)-eps_v/3.d0<br>      e3 = eps(3)-eps_v/3.d0</p><p>c ===============================<br>c ELASTIC STRESS UPDATE<br>c ===============================</p><p>      sig(1)=sig(1)+Kmod_d*eps_v+2.d0*Gmod_d*e1<br>      sig(2)=sig(2)+Kmod_d*eps_v+2.d0*Gmod_d*e2<br>      sig(3)=sig(3)+Kmod_d*eps_v+2.d0*Gmod_d*e3<br>      sig(4)=sig(4)+Gmod_d*eps(4)<br>      sig(5)=sig(5)+Gmod_d*eps(5)<br>      sig(6)=sig(6)+Gmod_d*eps(6)</p><p>c ===============================<br>c DRUCKER-PRAGER YIELD CHECK<br>c ===============================</p><p>      I1 = sig(1)+sig(2)+sig(3)</p><p>      s1 = sig(1)-I1/3.d0<br>      s2 = sig(2)-I1/3.d0<br>      s3 = sig(3)-I1/3.d0</p><p>      J2 = 0.5d0*(s1*s1+s2*s2+s3*s3)<br>     &     +sig(4)*sig(4)+sig(5)*sig(5)+sig(6)*sig(6)</p><p>      phi_r = phi*3.14159265358979d0/180.d0</p><p>      dp_a = 2.d0*dsin(phi_r)/(dsqrt(3.d0)*(3.d0-dsin(phi_r)))<br>      dp_k = 6.d0*coh*dcos(phi_r)/(dsqrt(3.d0)*(3.d0-dsin(phi_r)))</p><p>      f = dsqrt(J2 + tiny)-3.d0*dp_a*I1-dp_k</p><p>c ===============================<br>c RADIAL RETURN (STABLE)<br>c ===============================</p><p>      if (f.gt.0.d0) then</p><p>         scale = (3.d0*dp_a*I1+dp_k)/(dsqrt(J2)+tiny)</p><p>         sig(1)=sig(1)*scale<br>         sig(2)=sig(2)*scale<br>         sig(3)=sig(3)*scale<br>         sig(4)=sig(4)*scale<br>         sig(5)=sig(5)*scale<br>         sig(6)=sig(6)*scale</p><p>      endif</p><p>      endif<br>      endif</p><p>      return<br>      end. </p>

<p>Hi there, </p><p data-start="89" data-end="277">I need to stop an explicit simulation and restart it with a modified termination time. After reviewing the LS-DYNA documentation, I understand that a simple restart should be used. I would like to ask how the restart keyword file should be prepared. Should I copy the current input file, rename it, and modify the termination time, and then use it as the restart input file (i = restartinput, R = D3DUMPnn)?</p>

<p>Hi <br>According to my research, GPU acceleration is not available for the explicit LS-DYNA solver. However, I came across the following article on the NVIDIA website:<br>https://developer.nvidia.com/blog/advancing-ansys-workloads-with-nvidia-grace-and-nvidia-grace-hopper/ </p><p>The car crashing cannot be implicit so could you please clarify whether GPU acceleration is available for the explicit solver or not?</p>

<p>Hello,</p><p>Is it possible to simulate the FSI using CESE fluid solver with a structural component defined using SPH. If yes, which keywords are required to define coupling?</p><p>Regards,<br>Atish </p>

<p>Hi,</p><p>I downloaded input files for battery modelling from https://lsdyna.ansys.com/battery/#download. Some of them cannot be run due to different problems. </p><p>For the input file of Basic_intshort, it shows *** Error 10246 (KEY+246)<br>     line contains improperly formatted data<br>      *** Error reading *EM_MAT card.<br>          At line# 89 of file<br> --------------------------------------------------------------------------<br>          4         1<br> --------------------------------------------------------------------------<br> <br> *** Error 10450 (KEY+450)<br>     in keyword command:<br>         5         2    3.70e7<br>          At line# 90 of file<br>For the case of  Basic_socshift,   it shows</p><p> *** Error 10246 (KEY+246)<br>     line contains improperly formatted data<br>      *** Error reading *EM_MAT card.<br>          At line# 67 of file<br><br> --------------------------------------------------------------------------<br>          4         1<br> --------------------------------------------------------------------------<br> <br> *** Error 10450 (KEY+450)<br>     in keyword command:<br>         5         2    3.70e7<br>          At line# 68 of file<br> For the case of Meshless, it shows</p><p> *** Error 10307 (KEY+307)<br>     CHECKING MATERIAL INPUT Part ID= 1<br>     PART ID 1 has TMID= 0 which does not exist.<br>     This is PART 22 in the order of input.<br>     Coupled structural thermal analysis needs to have a thermal material ID defined.</p><p>There are different errors with other cases. I am using R16 solver, I wonder if these input files are old or other reasons. Thank you!</p>

<p>Hello everyone.<br>Please help me configure CONTROL_CONTACT so that Contact doesn't return calculation errors:</p><p></p><p>Thank you.</p>

<p><p>Hello everyone, I am modeling a reinforced concrete column under axial load applied as a rigid body load. I modeled the concrete using solid elements elform of 3 and hourglass type 3, for rebars I am using beam element. Concrete material is MAT072R3 and steel is MAT024. For bond between concrete and steel first I used Lagrange in solid but it was affecting the stress distribution in concrete then I switched to beam in solid which seems no issues in concrete stresses. However, I am not able to see the stress in rebar in either cases whether using Lagrange in solid or beam in solid. It seems the stress or axial force is not getting transferred to rebar because when running the simulation there is no movement in rebar. I did activate the extent binary keword by putting the value of BEAMIP to 1. I would appreciate your help to solve this issue I am facing. Please see attached photos for clarity.</p><p>  </p><p></p>

<p></p><p>I'm analysing the impact of a MAT_ELASTIC shell with S-ALE formulation but is not realistic.</p><p>A few steps after  the contact with water, the ALE element drops down before touching the shell. </p><p>I've tryed many different setups and keyword but the issue doesn't expire</p><p> </p><p> </p>