/DTPL

Optimization Keyword

/DTPL – Design Variable for Topology Optimization

Description

Defines parameters for the generation of topology design variables.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
/DTPL/dtpl_ID
title
grpart_ID	TMIN	STRESS	MEMBSIZ	PATRN	PATREP	EXTR	MESH	DRAW	MMOCID

TMIN =0/1, if TMIN=1., read thickness definition: T0

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
T0

STRESS=0/1, if STRESS =1, read stress constraint definition: MAXSTRS

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
MAXSTRS

MEMBSIZ=0/1, if MEMBSIZ =1, read member size constraint definition:

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
MINDIM		MAXDIM		MINGAP

PATRN=0/1, if PATRN =1, read pattern grouping constraint definition (Comment 2):

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
TYP	AID	XA		YA		ZA
	FID	XF		YF		ZF
UCYC	SID	XS		YS		ZS

PATREP =0/1/2,

If PATREP =1, read MASTER definitions for pattern repetition constraint (Comment 3):

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
ptrepCID
CAID	XCA		YCA		ZCA
CFID	XCF		YCF		ZCF
CSID	XCS		YCS		ZCS
CTID	XCT		YCT		ZCT

If PATREP =2, read SLAVE definitions for pattern repetition constraint (Comment 3):

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
masterID	SX		SY		SZ
ptrepCID
CAID	XCA		YCA		ZCA
CFID	XCF		YCF		ZCF
CSID	XCS		YCS		ZCS
CTID	XCT		YCT		ZCT

EXTRU=0/1, if EXTRU =1, read the extrusion constraint definition (Comment 4):

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
ETYP	extrGRN1	extrGRN2

MESH=0/1, if MESH =1, read mesh type definition:

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
MTYP

DRAW =0/1, if DRAW=1, read draw direction constraint definition (Comment 5):

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
DTYP	DAID	XDA		YDA		ZDA
	DFID	XDF		YDF		ZDF
ogrpart	NOHOLE	TSTAMP

MMOCID =0/1, if MMOCID=1, read skew identifier for mapping the design domains in Multi Model Optimization:

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
MCID

Field	Contents
dtpl_ID	Topology design variable identifier. (Integer > 0)
title	Title. (Character, maximum 100 characters)
grpart_ID	Part group identifier defining the design space. (Integer > 0)
TMIN	Indicates if minimum thickness definition is defined. Default = 0 (Integer) = 0: No = 1: Yes
T0	Minimum thickness (Real > 0.0)
STRESS	Indicates if the von Mises stress constraint is to be defined. (Integer) = 0: No = 1: Yes
MAXSTRS	Upper bound of the constraint on von Mises stress. No default (Real > 0.0)
MEMBSIZ	Active member size control flag. (Integer > 0) = 0: No = 1: Yes
MINDIM	Specifies the minimum diameter of members formed. This field can be used to eliminate small members. It also eliminates checkerboard results. Default = No Minimum Member Size Control (Real > 0.0)
MAXDIM	Specifies the maximum diameter of members formed. This field can be used to prevent the formation of large members. It can only be used in conjunction with MINDIM. Default = No Maximum Member Size Control (Real > 0.0)
MINGAP	Defines the minimum spacing between structural members formed. This command can only be used in conjunction with MAXDIM. Default = blank (Real > MAXDIM)
PATRN	Active pattern grouping flag. See Comment 2. (Integer) = 0: No = 1: Yes
TYP	Pattern grouping type requested. Default = No pattern grouping (Integer) = 1: 1-plane symmetry = 2: 2-plane symmetry = 3: 3-plane symmetry = 10: Cyclic = 11: Cyclic with symmetry
AID	Anchor node identifier for variable pattern grouping definition.. (Integer > 0 or blank) If blank, the XA, YA, and ZA fields should not be blank.
XA, YA, ZA	Coordinates of the pattern grouping anchor point. (Real or blank) If blank, AID should not be blank.
FID	Node identifier used to define the direction of the first vector for variable pattern grouping. (Integer > 0 or blank) If blank, the XF, YF, and ZF fields should not be blank.
XF, YF, ZF	Components of the first vector used to define pattern grouping. (Real or blank) If blank, FID should not be blank.
UCYC	Number of cyclic repetitions for cyclical symmetry. This field defines the number of radial "wedges" for cyclical symmetry. The angle of each wedge is computed as 360.0/UCYC. Default = blank (Integer > 0 or blank)
SID	Node identifier of the second point for pattern grouping definition. (Integer or blank) If blank, the XS, YS, and ZS fields should not be blank.
XS, YS, ZS	Coordinates of the second point for pattern grouping definition. (Real or blank) If blank, SID should not be blank.
PATREP	Indicates whether pattern repetition is defined and the type of pattern repetition. See Comment 3. (Integer) = 0: no pattern repetition = 1: pattern repetition is defined, and this design variable is master = 2: pattern repetition is defined, and this design variable is slave
masterID	Master /DTPL identifier for pattern definition. (Integer > 0) Only needed if PATREP =2.
SX, SY, SZ	Scale factors for pattern repetition in X, Y, and Z directions respectively. Default = 1.0 (Real > 0.0)
ptrepCID	Skew coordinate system identifier that defines the pattern repetition coordinate system. Default = 0 (Integer > 0)
CAID	Node identifier of the anchor point for the definition of a pattern repetition coordinate system. (Integer > 0 or blank) If blank, the XCA, YCA, and ZCA fields should not be blank.
XCA, YCA, ZCA	Coordinates of anchor point for the definition of a pattern repetition coordinate system. (Real or blank) If blank, CAID should not be blank.
CFID	Node identifier of the first point for the definition of a pattern repetition coordinate system. (Integer > 0 or blank) If blank, the XCF, YCF, and ZCF fields should not be blank.
XCF, YCF, ZCF	Coordinates of the first point for the definition of a pattern repetition coordinate system definition. (Real or blank) If blank, CFID should not be blank.
CSID	Node identifier of the second point for the definition of a pattern repetition coordinate system. (Integer > 0 or blank) If blank, the XCS, YCS, and ZCS fields should not be blank.
XCS, YCS, ZCS	Coordinates of the second point for the definition of a pattern repetition coordinate system. (Real or blank) If blank, CSID should not be blank.
CTID	Node identifier of the third point for the definition of a pattern repetition coordinate system. (Integer > 0 or blank) If blank, the XCT, YCT, and ZCT fields should not be blank.
XCT, YCT, ZCT	Coordinates of the third point for the definition of a pattern repetition coordinate system. (Real or blank) If blank, CTID should not be blank.
EXTRU	Active extrusion constraint flag. See Comment 4. (Integer) = 0: Not active = 1: Active
ETYP	Extrusion constraint type to be used. (Integer) = 0: NOTWIST. Indicates that the cross-section cannot twist around the neutral axis, in which case only one path needs to be defined. = 1: TWIST. Indicates that the cross-section can twist around the neutral axis, in which case two paths need to be defined.
extrGRN1	Node group identifier that defines the primary extrusion path. (Integer > 0)
extrGRN2	Node group identifier that defines the secondary extrusion path. (Integer > 0 or blank) If this field is blank, the secondary extrusion path is not specified. This is only required when ETYP=1 (TWIST) is defined.
MESH	Indicates that mesh type information is to follow. (Integer) = 0: Not active = 1: Active
MTYP	Indicates that the mesh conforms to certain rules for which the optimizer is tuned. Currently, only the ALIGN option is available. ALIGN indicates when manufacturing constraints are active, the mesh is aligned with the draw direction or extrusion path. (Integer) = 1: ALIGN
DRAW	Active draw/casting direction constraint flag. See Comment 5. (Integer) = 0: Not active = 1: Active
MMOCID	Skew identifier flag for mapping the design domains in Multi-Model Optimization. = 0: Not active = 1: Active
DTYP	Draw direction constraint type to be used. (Integer) = 1: Single die
DAID	Node identifier used for the definition of a draw direction anchor point. (Integer > 0 or blank) If blank, the XDA, YDA, and ZDA fields should not be blank.
XDA, YDA, ZDA	Coordinates of the draw direction anchor point. (Real or blank) If XDA, YDA, and ZDA are blank, DAID should not be blank.
DFID	Node identifier for the definition of a draw direction point. The vector is defined from the anchor point to this point. (Integer > 0 or blank) If blank, the XDF, YDF, and ZDF fields should not be blank.
XDF, YDF, ZDF	Direction of the vector for draw direction definition. These fields define a point. The vector is defined from the anchor point to this point. (Real or blank) If XDF, YDF, and ZDF are blanks, DFID should not be blank.
ogrpart	Part group identifier of non-designable parts, whose interaction with designable parts needs to be considered with regard to the defined draw direction. OBST stands for obstacle. Only recognized if DRAW flag is also present on same DTPL card. (Integer > 0 or blank) > 0: part group identifier of non-designable parts blank: this definition is not active.
NOHOLD	Flag preventing the formation of through-holes in the draw direction. Note that it does not prevent holes perpendicular to the draw direction. The assumed minimum thickness in the draw direction is twice the average mesh size. (Integer) = 0: control off = 1: control on
TSTAMP	Defines the thickness of the 3D shell structure into which the design is forced to evolve into. The recommended minimum thickness is three times the average mesh size. (Real > 0.0 or blank) If blank, the design is not forced to evolve into a 3D shell structure.
MCID	Skew identifier used for mapping the design domains in Multi-Model Optimization.

Pattern is activated with TYP=1 (1-plane symmetry)

dtpl_example

Pattern is activated and use TYP=1 (1-plane symmetry).

/DTPL/1

grpart 6 for topology optimization

### PATRN=1: active pattern

### TYP= 1: 1-plane symmetry

### AID=1: anchor node ID for variable pattern is 1

### FID=17: Node ID 17 used to define the direction of the first vector

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

#grpart_ID TMIN STRESS MEMBSIZ PATRN PATREP EXTR MESH DRAW

6 1

# TYP AID XA YA ZA

1 1

# FID XF YF ZF

# UCYC SID XS YS ZS

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

Draw and MMOCID is activated with TYP=1 (1-plane symmetry)

dtpl_example_mmocid

dtpl_example_mmo_topo

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

/DTPL/1

grpart 1 for topology optimization

### MEMBSIZ=1: active member size control

### DRAW=1: active draw/casting direction constraint

### MMOCID=1: active Skew identifier flag for mapping the design domains in Multi-Model Optimization

### minimum diameter of members MINDIM=40 and maximum diameter of members MAXDIM=80

### TYP= 1: 1-plane symmetry

### Normal vector is from Anchor node (XA,YA,ZA) to First node (XF,YF,ZF)

### MCID=1: Skew identifier 1 used for mapping the design domains in Multi-Model Optimization

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

#grpart_ID TMIN STRESS MEMBSIZ PATRN PATREP EXTR MESH DRAW MMOCID

1 1 1 1

# MINDIM MAXDIM MINGAP

40 80

# TYP AID XA YA ZA

1 0 0 0

# FID XF YF ZF

0 0 -1

# UCYC SID XS YS

# MCID

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

1.	For PATRN=1 (active pattern), there are five pattern grouping options:

1-plane symmetry (TYP = 1)

This type of pattern grouping requires the anchor point and first point to be defined. A vector from the anchor point to the first point is normal to the plane of symmetry.

dtpl_1_plane

2-plane symmetry (TYP = 2)

This type of pattern grouping requires the anchor point, first point, and second point to be defined. A vector from the anchor point to the first point is normal to the first plane of symmetry. The second point is projected normally onto the first plane of symmetry. A vector from the anchor point to this projected point is normal to the second plane of symmetry.

dtpl_2_plane

3-plane symmetry (TYP = 3)

dtpl_3_plane

Cyclic (TYP = 10)

This type of pattern grouping requires the anchor point, first point, and number of cyclical repetitions to be defined. A vector from the anchor point to the first point defines the axis of symmetry.

dtpl_cyclic_10

Cyclic with symmetry (TYP = 11)

This type of pattern grouping requires the anchor point, first point, second point, and number of cyclical repetitions to be defined. A vector from the anchor point to the first point defines the axis of symmetry. The anchor point, first point, and second point all lay on a plane of symmetry. A plane of symmetry lies at the center of each cyclical repetition.

dtpl_cyclic

For a more detailed description, refer to Pattern Grouping contained within the User's Guide Manufacturability for Topology Optimization section.

2.	PATREP =1, read MASTER definitions for pattern repetition constraint.

PATREP =2, read SLAVE definitions for pattern repetition constraint.

For a more detailed description, refer to Pattern Repetition for Topology Optimization.

3.	EXTRU =1, read the extrusion constraint definition. There are two types of extrusion constraints: ETYP=0 (non-twisted cross-section) and ETYP=1 (twisted cross-section).

dtpl_extru

For a more detailed description, refer to Extrusion Constraints for Topology Optimization.

4.	DRAW =1, read draw direction constraint definition. The type of draw direction that could be used is single die (DTYP=1).

dtpl_draw

For a more detailed description, refer to Draw Direction Constraints for Topology Optimization.

5.	This entry is represented as an optimization design variable in HyperMesh and HyperCrash.