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FEA and CFD Analysis

TrueGrid® Release Notes for Version 2.1.5

TrueGrid® Features New to Version 2.1.5, May 15, 2002

1. The SID dialogue has the dummy interface type (not merging of nodes only) moved to the main menu.
2. Certain types of face sets in the part phase cause TrueGrid® to crash. This has been fixed.
3. There was a bug in the way the element sets were being written to the ABAQUS, NASTRAN, ANSYS, and MARC outputs. This is fixed.
4. The BLEND4 and BLEND3 options of the SD command to define surfaces had a bug that was fixed. If the surface was essentially a ruled surface because two opposite edges were lines, then the projection may have failed.
5. The interactive graphics for the SPLINE 3D curve had a display bug when the end derivatives where specified.
6. The report from the merging (T, TP, and STP) may have been wrong if nodes had been deleted automatically due to element deletions.
7. When highlighting a command string and using the Control-z keys to re-display the dialogue box for the command failed when one of the arguments was a parameter. This has been fixed.
8. A bug was introduced in version 2.1 that would cause the x(i,j,k), y(i,j,k), and z(i,j,k) functions which would sometimes give the wrong results in an expression if the expression was used to define the new coordinates in a MA, PA, PB, PBS, MA, or MB command. This bug has been removed.
9. The variable beam thickness using the IBM/JBM/KBM commands in the part phase for LS-DYNA using an orientation vector which is normal to a given surface, with TrueGrid® running on the PC, may have output the incorrect thickness. This is fixed.
10. When using the SYMM option of the PLANE command, if the plane is not axisiplanes and the LS-DYNA keyword is the output, the node set associated with (first argument) the *BOUNDARY_SLIDING_PLANE might be wrong. This is fixed.
11. There was a bug in the UNIFM command used with an Intra-Part BB. If the two sides (master and slave) have a common edge and the master side is periodic, then the UNIFM could make the wrong connections an the smoothing would be obviously wrong. This would be rare. It is fixed.
12. There was a bug in the FVVS command which passed an illegal value to the arccos function. This bug has been fixed.
13. There was a bug in the window refreshing that caused TrueGrid® to crash. It occurs very rarely when the input switches from batch (input file) to interactive (using the menus) after the insprt command was executed. this is fixed.
14. The display of shell thicknesses in the merge phase (CO THIC) for the hide (DISP) graphics would only work for material 1. This is fixed.
15. There was an ESM bug introduced in the fix for version 2.1.4 that has been removed. It would cause TrueGrid® to crash.
16. The new BULC command locates an interior vertex of a butterfly structure based only the shape of the two exterior curves. The goal is to produce a pair of points from the two exterior curves and two additional points from this BULC command to form a trapizoid with angles 45, 45, 135, and 135 degrees. This command is needed twice to form the two interior points. The coordinates are saved in the parameters %xprj, %yprj, and %zprj. The point that is input is used to select the closest point on each of the two specified curves. Then a right isosceles triangle is fitted through these points in a plane that is nearly orthogonal to both curves. Actually, there are two such triangles that are formed. The orpt command is used to select one from this pair. Then the leg of the triangle that is closest to the initial point is chosen. A point is selected along this leg of the triangle so that the ratio of the leg of the resulting trapizoid and the base of the trapiziod matches the specified ratio.
BULC curve_1 curve_2 x y z ratio

TrueGrid® Features New to Version 2.1.4, Mar. 10, 2002


1. A bug was fixed when shell properties were substituted in the merge phase, including changing the material.
2. Shell normals were in error in the graphical fill mode. This is fixed.
3. The ANSD command had a bug that is now fixed.
4. Some trimmed surfaces had all edges lumped into 1. This has been fixed.
5. The ANSYS output option has been modified to allow for larger models. Now the limit is 99,999,999 nodes and elements.
6. A bug was fixed in the labeling of tokens in the hide mode of graphics. The problem occured when there were objects an extreme distance from the center of the picture and things were rotated.
7. There were rare cases where CAD/IGES surfaces failed to be trimmed the untrimmed surface was substituted. Many of these problems have been fixed.
8. There is a new pop-up option for colored filled polygon graphics postscript. One can now generate a 256 by 256 pixel image.
9. The merge phase deletion of brick elements had a new bug in it. This has been fixed.
10. Saved segments output for LS-DYNA keywprd output has been fixed.
11. There was a special case of the BB block boundary interface for cylindrical parts that failed. This is now working.
12. The deactivation/activation and output of boundary conditions and constraints that preceeded an update command are now functioning properly.
13. There was a bug in the ibm/jbm/kbm commands when the beam was degenerate. This has been fixed.
14. If a part was generated to invoke the ibm/jbm/kbm commands and then the part ignored using a material of 0, then the nodal constraints and boundary conditions would be ignored. This has been corrected.
15. There was a graphics bug when displaying degenerate BB block boundaries (an edge or vertex). This is now working.
16. There were some cases when creating a face set in the part phase from brick elements that would fail. This is fixed.
17. The help and dial commands did not work for a few commands. These commands should now work for all commands.
18. The new types of sliding interfaces for TOPAZ3D did not work. This has been fixed.
19. A bug was fixed for complex multi-regions for the RELAX, ESM, and UNIFM commands.
20. There was a bug with element sets for LS-DYNA and ALE3D outputs which was fixed.
21. The CSF command has been expanded to handle cross sections along an edge.
The before_or_after flag has been extended as follows:
0 if before the cross section that is a face (current)
1 if after the cross section that is a face (current)
2 if before the i-edge cross section (new)
3 if after the i-edge cross section (new)
4 if before the j-edge cross section (new)
5 if after the j-edge cross section (new)
6 if before the k-edge cross section (new)
7 if after the k-edge cross section (new)
22. Bugs in the dyna3d and lsdyna3d ouput for cross section force data have been fixed.
23. A bug in the FLUENT output was fixed.
24. A bug in the readmesh command for the NASTAN format for beams was fixed. Under the right conditions, the same node was read for both nodes of a beam.
25. The new DEF command is used to create a function. This function can then be used just like the intrinsic functions like SIN or MAX
i. in the desk calculator (DC),
ii. in mathematical expressions that are defined with the square brackets,
iii. in the logical expressions used by the IF and ELSEIF conditional statements,
iv. in equations X=, Y=, Z=, T1=, T2=, T3= where the mesh is directly modified,
v. and in function curves and surfaces.
The syntax for this new command is:
DEF name(x1,x2,...,xn)=expression
where the function name and the dummy arguments xi must start with an alphabetical character. Only the first 8 characters are used, so each must be unique in the first 8 characters.

EXAMPLE
def f1(a11,a21,a12,a22)=a11*a22-a21*a12
para k .7;
dc sqrt(1.1*f1(%k,.2,1/3,2))

26. The maximum number of curves and surfaces to be selected in a display list command has been increased from 1000 to 5000.
27. The LCD load curve definition command has been extended while preserving all old versions of the command. The new command looks like:
LCD ld_curve_# options_1 options_2 ;
where an option type 1 can be any set of
SIDR type
where tyoe can be:
0 for transient analysis or other
1 for stress initialization only
2 for stress initialization and transient analysis
SFA abscissa_scale_factor
SFO ordinate_scale_factor
OFFA abscissa_offset
OFFO ordinate_offset
DATTYP type
where type can be
0 for monotonic abscissa
1 for non-monotonic abscissa
where an option type 2 must be one of
LP t1 f1 t2 f2 ... tn fn ;
where ti fi are the points that form a polygonal curve
FUNC npnts u0 ux expression ;
where the curve will contain npnts points
where the algebraic function has the independent variable u
where u0 and ux defines the range for the independent variable u
Note that the LP option is like the old LCD, but without the keyword LP.
28. A bug involving undefined master block boundaries for slave TRBB has been fixed.

TrueGrid® Features New to Version 2.1.2, DEC. 24, 1996-2006


1. The 'tcrs' options for sliding interfaces now works with the OTOPAZ command.
2. Progressions in the history table are now truncated to 120 characters. If the progression extends beyond 120 characters the last character displayed in the progression is '*'.
3. The bug in PRESCRIBED VELOCITIES AND ACCELERATIONS has been fixed. This only affected the DYAN3D output option.
4. The was a bug regarding bounded planes in IGES format. This has been fixed.
5. There was a bug when reading certain IGES files with long ASCII strings in the header (GLOBAL) data. This has been fixed.
6. A class of IGES trimmed surfaces failed in the past because the trimming curve was out of the domain of the surface being trimmed. When this is a small error, TrueGrid® now ignores the problem on trims the surface.
7. Discrete beam cross sections for LSDYNA output now work. The main problem was with the dialogue box. If you have input files with discrete beam cross section definitions, you may need to repair them. The following key words should be used for the following purposes:
vold - volume
lump - lumped (geometric) inertia
cablcid - local coordinate system identifier
cabarea - cable area
caboff - cable offset

8. When transition elements (TRBB) are generated with pressures using pr and pramp, the transition element pressures may have been in error. This is fixed.
9. There was a bug in the history table that sometimes caused TrueGrid® to crash. This has been fixed.
10. Sliding interface type 46 (LSDYNA) is now fixed. Also, siinfo now prints information about many of the new sliding interface types.
11. A bug was fixed with the 2D curves LD option LD3D2D. This option in the past may have destroyed any 2D curves with numbers greater than those defined in this command.

TrueGrid® Features New to Version 2.1.1, NOV. 13, 1996-2006


1. A bug in the LSDYNA keyword output when using the FT or FTI command has been fixed.
2. Several material models for LSDYNA were fixed. This includes numbers 10, 71, and any numbered above 99.
3. The old TOPAZ3D output was re-installed. It is now referred to as otopaz3d. Be sure to change your output option to this to get the old format. You need to also change the options command from tz3dopts to otz3dops and the materials command from tz3dmats to otz3dmat.
4. A bug in the license manager for the PC was fixed. If you had trouble authorizing the license manager and received an error message saying that the lock file had been altered, it is possible that you need this new version of TGLM (TrieGrid® license manager).
5. A class of IGES surfaces based on conic curve sections was never supported by TrueGrid®. This has been corrected.
6. Certain types of very thin and long trimmed surfaces from an IGES file may have failed to tri. The aspect ratio would have to have been greater than 500. This been fixed.
7. The resolution of the swept surface can now be controled with the GETOL command. A resolution less than 1 will improve the resolution.
8. There were a few IGES files whose headers were not readable by TrueGrid®, v2.1. This has been corrected.
9. There was a minor compiler bug that affected only the PC version. It caused a floating point exception in a few cases. A work about the compiler bug fixed this problem.
10. The LSDYNA *CONTACT_TIEBREAK_NODES_ONLY card now includes *SET_NODE_COLUMN instead of *SET_NODE_LIST.
11. If there were more than 2048 characters in the union of transformations for the LCT, GCT, LEVCT, or geometric transformations, TrueGrid® would crash. This has been fixed.
12. The maximum number of parameters allowed has been increased to 5000.

TrueGrid® Features New to Version 2.1.0, August 30, 1996-2006


1. The PB and PBS commands can be used on the slave side of an intra-part BB command to place any of the corners of the interface. This applies to the use of the mouse to place vertices as well. The interior vertices can only be positioned from the master side of the interface. If there is a normal offset applied to the slave side, this feature will not work.
2. The computational window contains three index bars used heavily to select portions of the mesh. They are now labeled so that one can easily identify the I-, J-, and K-index bars. The partitions are also numbered along each of the bars.
There is a new command to control these reduced index labels in the computational window.
RINDEX option
where option can be ON or OFF
The default is ON.
3. The Merge Phase command SPWF creates LS-DYNA spot welds for material 100.
SPWF points
sw_material 1st_contact 2nd_contact
where points can be
EQSP 3D_curve_# flag #_spotwelds
where flag can be
0 to include the last point
1 to not include the last point
PNTS 3D_curve_# flag
where flag can be
0 to include the last point
1 to not include the last point
RT x y z (Cartesian coordinates)
CY rho theta z (cylindrical coordinates)
SP rho theta phi (spherical coordinates)
where 1st_contact and 2nd_contact can be
MAT material_number
Use the CO SPWF feature to view each spot weld.
4. The IGES and IGESFILE commands now supports trimmed infinite planes.
5. The new command ESM, for Elliptic SMoothing, works with the intra-part BB command to smooth the mesh across seams between disjoint blocks. This is applicable only to 2D faces of the mesh. It produces an ideal mesh when a butterfly topology is used. This method produces a smooth mesh around the triple point. It has the affect of attracting the mesh lines toward the triple point. Because of this, the last two parameters define symmetric source terms in the system of elliptic differential equations, countering the attraction to the triple point. Care should be taken in choosing these two values.
This feature can also be applied to the cases where four or five faces come together and surround a common point. In the case of a quad point, no source terms are applied to the differential equations in the area of the quad point. The opposite effect occurs with a quintuple point, with the mesh lines naturally repelled by a quintuple point. For this reason, the amplitude factor (alpha) should be negative in the ESM command to compensate.
ESM i1 j1 k1
i2 j2 k2 [& im jm km in jn kn] #_iterations min_change weight alpha beta
Many regions can be specified. Each region 'im jm km in jn kn' is preceded by '&'. The parameters '#_iterations min_change weight' are the same as RELAX. The last two parameters define the exponential decay of the source terms in the elliptic equations. The function used is
alpha*exp(-beta*rho)
where rho is the logical distance of a node to the triple or quintuple point. Only faces sharing the triple or quintuple point are biased this way. These terms are clipped so that only nodes inside an ellipse about the triple quintuple point are assigned non-zero values. This produces a smooth mesh with nodes repelled from the triple or quintuple point.
It is essential that the intra-part BB command be used to glue edges or faces together so that TrueGrid® knows how to bridge across disconnected blocks.
6. The RELAX command has been extended so that multiple regions that may be glued together with the intra-part BB commands, can be relaxed. Unlike the ESM, no source terms are used in the solution to the elliptic differential equations. This extension only applies to faces of the mesh.
RELAX i1 j1 k1 i2 j2 k2 [& im jm km in jn kn] #_iterations min_change weight
Many regions can be specified. Each region 'im jm km in jn kn' is preceded by '&'. It is essential that the intra-part BB command be used to glue edges or faces together so that TrueGrid® knows how to bridge across disconnected blocks.
7. The new ESMP command works with the ESM command. It defines addition source terms along an edge.
ESMP i1 j1 k1
i2 j2 k2 flag type parameter(s)
where flag can be
0 for the first node as the source of attraction
1 for the last node as the source of attraction
where type and parameter(s) can be
1 amplitude for linear
2 amplitude for cubic
3 amplitude for cosine
4 amplitude decay for exponential
where linear requires an amplitude
where cubic requires an amplitude
where cosine requires an amplitude
where amplitude requires an amplitude and a decay factor
Any edge in the region of relaxation can be assigned sources. A smoothly interpolated source will be superimposed on the source functions of the elliptic P.D.E.s being solved. If the parameter r is the relative distance from the point source, then the interpolation used for the source values is:
The linear function is amplitude*(1-r).
The cubic function is amplitude*(2*r**3-3*r**2+1).
The cosine function is amplitude*(cosine(r*pi)+1).
The exponential function is amplitude*exp(-decay*r).
8. There is a new SPW command to generate spotwelds for LS-DYNA and NASTRAN. This will generate the
*CONSTRAINED_SPOTWELD
and
*CONSTRAINED_SPOTWELD_FILTERED_FORCE
cards in LS-DYNA. Use the SPWD command to define the properties of the spotwelds. When doing so, be sure to specify both the number of force vectors and the time window to activate the filtered force card.
For NASTRAN, the RBE2 card is generated.
SPW id option nodes ;
where id is a positive integer identifying the spot weld
where an option can be
SPWD spwd_id
where a node can be
ANN node_# which can be any literal node number
NODE node_# which must be an existing node number
LOC x0 y0 z0 material_# to locate closest node
LOCC x0 y0 z0 material_# to locate closest node and change its
Use the CO SPW feature to view each spot weld.
9. A new surface type 'r3dc' has been added which defines a surface of revolution of a 3D curve around an arbitrary axis from a beginning angle to an ending angle.
r3dc x0 y0 z0 xn yn zn 3d_curve theta_begin theta_end; trans;
where
(x0,y0,z0) is a point on the axis of rotation.
(xn,yn,zn) is the vector parallel to the axis of rotation.
3D_curve is the 3D curve being rotated (generatrix).
theta_begin is the beginning angle for the rotational sweep.
theta_end is the ending angle for the rotational sweep.
trans is an optional transformation at the end.
10. The NDIGITS command can be used to specify the number of digits to write the output file for the CFX4 output option. The default is 7 and the minimum is 5.
11. A new command specifies the default interpolation during the part generation phase.
INTYP option
where option can be
1 for linear interpolation (default)
2 for transfinite interpolation
12. There is a new pair of interpolation commands for the Part Phase. These commands have the unique property that the interpolation is treated as an initialization. This is not a constraint like the LIN and LINI commands. The interpolation is done before edges are attached and before faces are projected to surfaces.
ILIN
ILINI
13. The ANSYS output option allows for element types SOLID73, SHELL93 and SOLID95. Be sure to assign parameters to the material model and use the QUADRATIC command before the parts using this material. To switch back to 1st order elements, use the command LINEAR before the part command.
In addition, it is possible to generate wedge, pyramid, and tet elements. Be sure to merge the nodes when generating the degenerate elements by using a command like STP in the Merge Phase. Only when appropriate nodes of an element are the same numbers, does the ANSYS output module know to configure the element as a wedge, pyramid, or tet element.
14. A new feature was added to the Composite Curve entity (102) in the TrueGrid® IGES module. Now a composite curve entity, which glues together a group of curves, can include another composite curve as one of the component curves. This is standard. This may make it possible for the IGES or IGESFILE commands to read an IGES file that it was not able to read before.
15. Face sets can be used to define sliding interfaces and other types of boundary conditions while in the Merge Phase. These new commands are:
Sliding interfaces - both linear and quadratic
SI FSET set_name interface_# boundary options ;
where boundary can be
M for master side
S for slave side
where an option can be
FAIL norm_failure_force shear_failure_force
EXP norm_failure_exp shear_failure_exp
FSF coulomb_friction_scale viscous_friction_scale
Pressure
PR FSET set_name load_# amplitude
Flux
FL FSET set_name load_# amplitude
Convection
CV FSET set_name first_ld_# first_amplitude second_ld_# second_amplitude exponent
Radiation Boundary condition
RB FSET set_name first_ld_# first_amplitude second_ld_# second_amplitude
Radiation Enclosure
RE FSET set_name 0 temperature obstruction
where the obstruction flag is
YES to include surface obstruction calculations
NO not to include surface obstruction calculations
Electric Flux
EFL FSET set_name value_of_flux
Bulk Fluid
BF FSET set_name bulk_# load_# amplitude exp_a exp_b
Non-Reflecting Boundary
NR FSET set_name
Symmetry Plane with Failure
SYF FSET set_name symmetry_plane_# failure
Saved Segment Interface
ISS FSET set_name
Convection Thermal Load
CVT FSET set_name coefficient temperature
Boundary Velocity
BV FSET set_name fx fy fz for NEKTON
Outlet
OL FSET set_name for FLUENT and NEKTON
Inlet
IL FSET set_name for FLUENT and NEKTON
Some of these commands are oriented. Use the ORPT command found in the SETS menu to control the orientation of the faces when the face sets are created.
16. There is a new interactive 3D Curves feature to optimize the creation of a composite curve formed by selecting edges of surfaces. This command is COEDG in the 3D Curves menu. The first step in using this new feature is to select the first surface edge. Based on this selection, the next likeliest surface edge in the picture will be highlighted. If this is the next desired edge, then the Yes button should be clicked on. Otherwise, an alternative must be selected. This process continues until all of the desired edges in the proper order have been selected. If the likeliest next edge is always the next edge, one can create such a composite curve very quickly simply by clicking on the Yes button for each component.
17. The History feature in the Part Phase has been improved. It now has a separate window which is constantly maintained. This table of previously issued commands is easy to use in locating commands that are in error, isolating over and under constrained parts of the mesh, activating and deactivating commands, and understanding the resulting mesh. This tool can turn what appears to be a difficult bug in the input into a few mouse clicks to determine the problem. The GUI for this feature is intuitive.
18. There is a new command to rotate and translate any surface.
TRSD surface_# trans ;
where trans can be any combinations of the following standard TrueGrid operators
MX x_offset
MY y_offset
MZ z_offset
V x_offset y_offset z_offset
RX theta
RY theta
RZ theta
RAXIS angle x0 y0 z0 xn yn zn
RXY
RYZ
RZX
TF origin x-axis y-axis
FTF 1st_origin 1st_x-axis 1st_y-axis 2nd_origin 2nd_x-axis 2nd_y-axis
INV
19. The READMESH now reads most of the data in a DYNA3D input file and enters the data into the TrueGrid internal data base. This makes it possible to modify the model or add more conditions before writing a output file.
20. There is a new FLUENT output option supporting the latest unstructured FLUENT. There is a new set of commands to support this new FLUENT output option. These commands set the boundary conditions. Note that the FBC (the first command below) and FBCI commands are in the Part Phase and the FBC (third command below) is in the Merge Phase.
FBC i1 j1 k1 i2 j2 k2 type zone
FBCI i_list; j_list; k_list; type zone
FBC FSET set_name type zone
where type can be
INTERIOR
WALL
PR_INLET for pressure-inlet
INLET_VE for inlet-vent
INTAKE_F for intake-fan
PR_OUTLE for pressure-outlet
EXHAUST_ for exhaust-fan
OUTLET_V for outlet-vent
SYMMETRY
PER_SHAD for periodic-shadow
PR_FAR_F for pressure-far-field
VELOCITY for velocity-inlet
PERIODIC
FAN
POROUS_J for porous-jump
RADIATOR
MASS_FLO for mass-flow-inlet
INTERFAC for interface
OUTFLOW
AXIS
21. When a node is constrained to be on more than 1 local symmetry planes, TrueGrid creates a new symmetry plane so that the combined symmetries can be specified with one constraint.
22. There are many improvements to the LS-DYNA output option. These include support for the thermal materials, new contacts, and control cards.
23. There are two new Merge Phase commands to support nodal follower forces.
The first command assigns a concentrated nodal load with a follower force. A follower plane is defined using three nodes. The normal of the plane defines the direction of the force. This is used for DYNA3D and LS-DYNA.
FFC nodes load_# amplitude node_1 node_2 node_3
where nodes can be
N node_number
RT x y z
CY rho theta z
SP rho theta phi
NSET name_of_set
Use the CO Merge Phase command with the FFC option to view this condition.
The second command assigns a follower nodal moment. A follower plane is defined using three nodes. The moment is about the normal of the follower plane. This is used for LS-DYNA.
FMOM nodes load_# amplitude node_1 node_2 node_3
where nodes can be
N node_number
RT x y z
CY rho theta z
SP rho theta phi
NSET name_of_set
Use the CO Merge Phase command with the FMOM option to view this condition.
24. There is a new command to generate prescribed rotational boundary conditions. A condition can be a velocity, acceleration, displacement, or a nodal rotation. This is suited for DYNA (velocities, accelerations, and nodal rotations) and LS-DYNA. In these codes, the selected nodes are prescribed this condition relative to an axis of rotation.
These commands can only be executed in the Part Phase.
FRB i1 j1 k1 i2 j2 k2 load_# amplitude options condition direction
where options can be any of the following
BIRTH time
DEATH time
OFFSET offset_1 offset_2
where condition must be one of the following
V for velocities
A for accelerations
D for displacements
DOFV for nodal DOF velocities
DOFA for nodal DOF accelerations
DOFD for nodal DOF displacements
where direction must be one of the following
X for about the x-axis
Y for about the y-axis
Z for about the z-axis
V x0 y0 z0 for about an arbitrary axis
EX for not about the x-axis
EY for not about the y-axis
EZ for not about the z-axis
EV x0 y0 z0 for not about an arbitrary axis
FRBI i_list; j_list; k_list; load_# amplitude options condition direction
where options can be any of the following
BIRTH time
DEATH time
OFFSET offset_1 offset_2
where condition must be one of the following
V for velocities
A for accelerations
D for displacements
DOFV for nodal DOF velocities
DOFA for nodal DOF accelerations
DOFD for nodal DOF displacements
where direction must be one of the following
X for about the x-axis
Y for about the y-axis
Z for about the z-axis
V x0 y0 z0 for about an arbitrary axis
EX for not about the x-axis
EY for not about the y-axis
EZ for not about the z-axis
EV x0 y0 z0 for not about an arbitrary axis
This command can only be executed in the Merge Phase.
FRB nodes load_# amplitude options condition direction
where nodes can be
N node_number
RT x y z
CY rho theta z
SP rho theta phi
NSET name_of_set
where options can be any of the following
BIRTH time
DEATH time
OFFSET offset_1 offset_2
where condition must be one of the following
V for velocities
A for accelerations
D for displacements
DOFV for nodal DOF velocities
DOFA for nodal DOF accelerations
DOFD for nodal DOF displacements
where direction must be one of the following
X for about the x-axis
Y for about the y-axis
Z for about the z-axis
V x0 y0 z0 for about an arbitrary axis
EX for not about the x-axis
EY for not about the y-axis
EZ for not about the z-axis
EV x0 y0 z0 for not about an arbitrary axis
Use the FRB option in the CO Merge Phase command in the Merge Phase to display these conditions.
25. The FD, ACC, and FV commands have been modified to support the LS-DYNA options. These commands now support the following:
EXLUDE to exclude normal directions BIRTH time DEATH time
26. The diagnostic commands mass, tmass, and pmass commands in the merge phase and the tmm density command have been upgraded to handle the materials defined for ABAQUS, ALE3D, ANSYS, DYNA3D, ENIKE3D, ES3D, NASTRAN, LS-DYNA, LSNIKE, MARC, NEUTRAL, NIKE3D, and TOPAZ3D.
27. The LS-DYNA rigid material model has additional parameters to specify Boundary Prescribed Motions. These options are available through the LSDYMATS command in the Control Phase. These options are activated using the BPM option and can be repeated with up to 6 different conditions.
BPM options ;
where an option can be
DOF flag
where flag can be
1 for x-translational degree-of-freedom
2 for y-translational degree-of-freedom
3 for z-translational degree-of-freedom
4 for translational motion in the given vector direction (use V)
5 for x-rotational degree-of-freedom
6 for y-rotational degree-of-freedom
7 for z-rotational degree-of-freedom
8 for rotational motion about the given vector (use V)
9 for degree-of-freedom rotation about x-axis (use OFFSET)
-9 for degree-of-freedom radial about x-axis (use OFFSET)
10 for degree-of-freedom rotation about y-axis (use OFFSET)
-10 for degree-of-freedom radial about y-axis (use OFFSET)
11 for degree-of-freedom rotation about z-axis (use OFFSET) -11 for degree-of-freedom radial about z-axis (use OFFSET)
VAD flag
where flag can be
0 for velocity
2 for displacement
3 velocity versus displacement
4 relative displacement
LCID load_curve_#
SF scale_factor
V x0 y0 z0
BIRTH time
DEATH time
OFFSET offset_1 offset_2
MRB rigid_material_#
NODES node+1 node_2
Note that some combinations of these parameters are not meaningful. If you are not sure, use the LSDYMATS dialogue box to step you through these options.
The old options RBV and RBD can still be used but they are no longer found in the dialogue box.
The DYNA3D rigid material model has additional parameters to specify Boundary Prescribed Motions. These options are available through the DYNAMATS command in the Control Phase. These options are activated using the BPM option and can be repeated with up to 6 different conditions.
BPM options ;
where an option can be
DOF flag
where flag can be
1 for x-translational degree-of-freedom
2 for y-translational degree-of-freedom
3 for z-translational degree-of-freedom
4 for translational motion in the given vector direction (use V)
5 for x-rotational degree-of-freedom
6 for y-rotational degree-of-freedom
7 for z-rotational degree-of-freedom
8 for rotational motion about the given vector (use V)
LCID load_curve_#
SF scale_factor
V x0 y0 z0
Note that some combinations of these parameters are not meaningful. If you are not sure, use the DYNAMATS dialogue box to step you through these options.
The old option RBV can still be used but it is no longer found in the dialogue box.
28. Additional LS-DYNA Control Cards are being added in support of version 960. These include:
CONTROL_CFD_GENERAL
for setting the general Navier-Stokes flow solver parameters,
including the following options:
INSOL sets the solver type to
0 for the default (INSOL=3)
1 explicit, transient, incompressible Navier-Stokes
3 semi-implicit, transient, incompressible Navier-Stokes
DTINIT sets the initial time step
CFL sets the maximum advective grid-CFL number
ICKDT sets the Reynolds and advective CFL check/report interval
ISTATS sets the level of statistics to report
0 don't collect any statistics
1 generate mean quantities
2 generate second moments in addition to mean quantities
TSTART set the statistics gathering start time
IAVG set the statistics reporting interval
CONTROL_CFD_MOMENTUM
for setting the momentum equation parameters in the N-S solver
IMASS selects the mass matrix formulation
0 IMASS=1 (the default)
1 Lumped mass matrix
2 Consistent mass matrix
IBTD toggles the use of the balancing tensor diffusivity
0 BTD=1 (the default)
1 BTD is on
2 BTD is off
IFCT toggle the use of the advective flux limiting advection scheme
0 IFCT=1 (the default)
1 advective flux limiting is on
2 advective flux limiting is off
DIVU set the RMS divergence tolerance
THETAK time weighting for viscous/diffusion terms
THETAA time weighting for advection terms
THETAF time weighting for body forces and boundary conditions
MOSOL momentum equations solver type
0 = 20 = default (Jacobi preconditioned conjugate gradient method
MAXIT maximum number of iterations
ICHKIT set the convergence check interval
IWRT activate the output of diagnostic information
0 diagnostic information is off (default)
1 diagnostic information is on
IHIST activate convergence history file generation
0 convergence history is off (default)
1 convergence history is on
EPS set the convergence criteria
IHG set the type of hourglass stabilization type
0 IHG=1 (default)
1 LS-DYNA CFD viscous hourglass stabilization
2 gamma-hourglass stabilization viscous form
CONTROL_CFD_PRESSURE
for setting the pressure solver parameters in the N-S solver
IPSOL Set the pressure solver type
0 IPSOL=22 for serial, IPSOL=21
10 Sparse direct solver
20 Jacobi preconditioned conjugate gradient method
21 SSOR preconditioned conjugate gradient method
22 SSOR method using Eisenstat transformation
MAXITER Set the maximum number of iterations for the pressure solver
ICHCIT Set the convergence criteria check interval
IDIAG Activate diagnostic output
IHST Activate convergence history file generation
EPSP Set the convergence criterion
NVEC Set the number of A-conjugate vectors to use
ISTAB Set the stabilization type
0 ISTAB=1 (default)
1 Local jump stabilization
2 Global jump stabilization
-1 No stabilization is active
BETA Set the stabilization parameter
CONTROL_CFD_TRANSPORT
for setting the momentum equation parameters in the N-S solver
ITEMP toggle energy equation and terms
0 No energy equation (default)
1 Energy equation solved in terms of temperature
2 Energy equation solved in terms of enthalpy
NSPEC activate NSPEC species transport equations (NPSEC <= 10)
IMSS select the mass matrix formulation
0 IMASS=1 (default)
1 Lumped mass matrix
2 Consistent mass matrix
IBALTD Toggle the use of balancing tensor diffusivity
0 BTD=1 (default)
1 BTD is on
-1 BTD is off
IAFLX Toggle the use of advective flux limiting
0 IFCT=1 (default)
1 Advective flux limiting is on
-1 Advective flux limiting is off
THETK Time weighting for viscous/diffusion terms
THTAA Time weighting for advection terms
THETF Time weighting for body forces and BCs
ITSOL Set equation solver type
MXITER Set the maximum number of iterations
ICKINT Set convergence criteria check interval
IDIAGN Activate the output of diagnostic information
ICHIST Activate the generation of a convergence history file
EPST Set the convergence criteria for the equation solver
IHGT Set hourglass stabilization type
0 IHGT=1 (default)
1 LS-DYNA CFD viscous hourglass stabilization
2 gamma-hourglass stabilization viscous form
EHGT Set stabilization parameter
CONTROL_CFD_TRANSPORT
ITRB Select the turbulence model
0 Turbulence models disabled
1 Smagorinsky LES sub-grid scale model
101 Spalart-Almaras model
SMAGC Set the Smagorinsky constant
CONTROL_COARSEN
ICOARSE Set the coarsening flag.
0 Do not coarsen (default)
1 Coarsen mesh
FANGL Set the allowable flatness angle
NSEED Set the number of seed nodes (optional)
SN1-SN8 Optional seed nodes.
CONTROL_IMPLICIT_GENERAL
Additional support was added for the new version 960 parameters:
CNSTN Indicator for consistent tangent stiffness
0 Do not use (default)
1 Use
FORM Element formulation when using IMFORM flag
0 Type 16
1 Type 6
CONTROL_IMPLICIT_EIGENVALUE
NEIG Number of eigenvalues to extract
SHIFT Shift frequency
CONTROL_SOLID
ESORT Automatic sorting of tetrahedron, etc. flag
0 No sorting required (default)
1 Full sorting
and one non-control card:
DAMPING_RELATIVE Apply damping relative to the motion of a rigid body.
CDAMP Fraction of critical damping
FRQ Frequency at which CDAMP is to apply
PIDRB Material (part) ID of rigid body
PSID Material (part) set ID.
29. The ANSD command has been extended to trimmed surfaces and polygon surfaces.
30. There is a new feature for detecting gaps in the merging process.
LABELS CRACKS angle
31. The CURTYP command controls the type of curve attachment used when the attach button is selected in the environment window.
CURTYP type
where type can be
CUR
CURS
CURE
CURF
The default is CURS
32. The AUTODYN output option now supports shell transition elements generated with the TRBB command.
33. The interpolation of quadratic nodes - the intermediate nodes when the QUADRATIC command is issued - has been improved.
34. The new SPOTWELD option in the menus is an easy interactive way to create multiple spot welds using the mouse to click on the nodes. This button is found in the boundary menu in the Merge Phase.
35. The new SPWD command defines the properties of aa spotweld. These definitions are needed by the SPW command and the associated interactive command SPOTWELD.
SPWD id options ;
where
id is a positive integer identifying the spot weld properties definition
where an option can be
DX for a displacement in the x-direction for all nodes
DY for a displacement in the y-direction for all nodes
DZ for a displacement in the z-direction for all nodes
RX for a rotational about the local x-axis for all nodes
RY for a rotational about the local y-axis for all nodes
RZ for a rotational about the local z-axis for all nodes
SN nornal_force
SS shear_force
N normal_force_exponent
M shear_force_exponent
TF failure_time
EP effective_plastic_strain
NF #_force_vectors
TW time_window
36. Block boundary interfaces can now be displayed within the part where the master side is defined. This facilitates specifying the intra-part BB command. These interfaces can also be labeled just as the other interfaces are. Their display and labeling work in the same way the other interfaces are labeled and displayed.
One can select interfaces using the lasso and by clicking on the label. The Display List panel in the environment window can be used in conjunction with mouse selection of interfaces to display a subset of the interfaces.
If one interface is selected using the mouse either with the lasso or by clicking on a label of an interface, then the attach button can be used to glue a selected region of the mesh to the master side. This, of course, only applies to the Part Phase where slave faces are glued to master faces of the mesh.
37. The new command errmod command has two options at this time:
ERRMOD mode
where mode can be
0 (default) error handling
2 for error interrupt mode
These options only affect the way TrueGrid handles errors in the batch mode. If the mode 2 is selected, then when an error in the input is encountered, TrueGrid will become interactive as though it had encountered an interrupt command in the batch file. Any problems due to the error can then be fixed interactively. Then the resume command can be issued to continue the batch command file.
This is not easy to do sometimes. Here are three cases that one should be aware of:
1. The command in the batch file is in error and it has many arguments. Any arguments that remain after the error is detected must still be processed once the resume command is issued. These arguments will also cause an error and a subsequent interrupt. WARNING: Do not try to modify the command file at this stage. It will only cause more problems since this command file is being buffered.
2. Some errors are not detected until the endpart command is encountered in the batch file. This will cause the part to be completed with errors. Then the interactive mode will be entered in the control phase. There will be little that can be done abut the part at this stage, but you will be able to proceed with a resume command if you wish.
3. When an insprt command is encountered, errors in some previously issued commands, such as the BB and TRBB commands, may be detected. This is because the insprt command, like the endpart command, cause the entire mesh to be re-calculated.
These limitations are not permanent. It is planned that the way batch errors are handled will be improved. This easy fix to the problem is being offered as a stop gap feature until the entire problem of error handling in the batch mode can be reworked.
38. In the merge phase the following DIAGNOSTIC options have been modified to catch illegal elements
ORTHOGON: -91 means an illegal element
SMALLEST: -1 means an illegal element
ASPECT: -1 means an illegal element
The ELM will flag these elements if explicitly asked,e.g.
if MEASURE ORTHOGON returns a minimum angle of -91 ELM -91 -91 will highlight the illegal elements
Further, ORTHOGON now only looks at the rectangle angles.
39. In the merge phase the TRIANGLE has been added as a DIAGNOSTIC option to measure the deviations of triangle angles from 60 degrees (-91 means an illegal element)
40. There are several new parameters.
%xcrprod, %ycrprod, %zcrprod are the components of the cross product function crprod
%inprod is the result of the inner product function inprod
%distance is the result of the distance function
%subang is the result of the subtended angle function subang
41. The VERBATIM command records data and writes it to the output file. This is only for keyword formatted output options where the order of cards is not important. The command is followed by the data on the next line of input. This storing of the data is stopped as soon as the ENDVERBATIM is encountered in the input stream to TrueGrid. For example:
VERBATIM
*BOUNDARY ...
*CONTACT ...
ENDVERBATIM
42. The VD command has new options. A volume can now be a box. These boxes are used to define boxes in LS-DYNA.
43. Duplicate nodes are filtered out in the follow output formats. The first 10 occurrences are listed and a count of the number of duplications are printed for each of the cases in the DYN3D and LS-DYNA output formats listed below.
DYNA3D
a. Multiple occurrences of a node on a sliding interfaces.
b. Nodes occurring on multiple Rigid Wall Cards.
c. Multiple occurrences of a node on a nodal load curve in Concentrated Nodal Loads and Follower Forces.
d. Multiple occurrences of a node on a velocity curve in Initial Conditions.
e. Multiple occurrences of a node on a velocity curve in Prescribed Velocities and Accelerations.
f. Multiple occurrences of a node on a temperature load curve in Temperature Input Option I.
g. Multiple occurrences of a node on a cross section in Cross Sections for Forces.
h. Multiple occurrences of a node in Momentum Deposition in Solid Elements.
i. Multiple occurrences of a node on a 1D slide line in One Dimensional Slidelines.
LS-DYNA KEYWORD
a. Multiple occurrences of a node on a cross section in Cross Sections for Forces.
b. Multiple occurrences of a node on a nodal load curve in Concentrated Nodal Loads and Follower Forces.
c. Multiple occurrences of a node on a velocity curve in Prescribed Velocity/Acceleration/Displacement.
d. Nodes occurring on multiple Rigid Wall Cards.
e. Multiple occurrences of a node on a temperature load curve in Load Thermal Variable Node.
f. Multiple occurrences of a node on a temperature load curve in Boundary Temperature Conditions.
LS-DYNA FIXED a. Nodes occurring on multiple Rigid Wall Cards.
b. Multiple occurrences of a node on a nodal load curve in Concentrated Nodal Loads and Follower Forces.
c. Multiple occurrences of a node on a velocity curve in Prescribed Velocity/Acceleration/Displacement.
d. Multiple occurrences of a node on a temperature load curve in Temperature Input Option I.
e. Multiple occurrences of a node on a temperature load curve in Temperature Boundary Conditions.
f. Multiple occurrences of a node in Momentum Deposition in Solid Elements.