Design Response
Description: Defines a structural response used in design optimization analysis either as a constraint or an objective.
Format:
Example:
| Field | Definition | Type | Default |
|---|---|---|---|
| ID | Design response identification number. | Integer > 0 | Required |
| LABEL | User-defined label. | Character | |
| RTYPE | Response type. See table below and Remark 5. | Character | Required |
| REGION | Topology design region identification number. See Remark 2. | Integer > 0 or blank | All TOPVAR regions |
| ATTA, ATTB, ATTC | Response attributes. See table below and Remarks 4 and 6. | Integer > 0 or Real or Blank |
| Response Type | Description | Response Attributes | ||
|---|---|---|---|---|
| RTYPE | ATTA (Integer > 0) | ATTB (Integer > 0) | ATTC (Integer > 0) | |
| COMP | Compliance. | Blank | Blank | Blank |
| COMPINDX | Compliance index. | Blank | Blank | Blank |
| FRMASS | Mass or volume fraction. | Blank | Blank | Blank |
| FREQ | Natural frequency. | Mode number | Blank | Blank |
| EIGN | Eigenvalue. | Mode number | Blank | Blank |
| LAMA | Buckling load factor. | Mode number | Blank | Blank |
| DISP | Displacement. | Component Number (1 - 6) | Blank | Grid Identification Number |
| SPCF | Single point constraint force. | Component Number (1 - 6) | Blank | Grid Identification Number |
| GLBSTRS | Global stress. | Blank | Blank | Blank |
| TEMP | Temperature. | Blank | Blank | Grid Identification Number |
| HFLOW | Heat flow. | Blank | Blank | Grid Identification Number |
| GLBTAVE | Global average temperature. | Blank | Blank | Set Identification Number |
| GLBTVAR | Global temperature variation. | Blank | Blank | Set Identification Number |
| GLBTEMP | Global temperature. | Blank | Blank | Set Identification Number |
| GLBDISP | Global displacement. | Component Number (1-6) | Blank | Set Identification Number |
Remarks:
- DRESP1 identification numbers must be unique.
- REGION is used to specify which design region a constraint is applicable to. It is ignored when RTYPE is set to COMP, DISP, or SPCF. If REGION is zero or blank, all TOPVAR regions will be used for FRMASS, COMP, or GLBSTRS.
- The initial constraint value used for FRMASS is the value specified on the TOPVAR entry.
- For DISP and SPCF the default for ATTC is the grid point with the largest absolute value in the component direction specified. If ATTA is also blank, the component defaults to the direction with the largest absolute value.
- Compliance index is defined as the ratio of the initial compliance of the unmodified model over the compliance of the modified one. For example, a compliance index of 2.0 would be that of a structure that is 1/2 the stiffness of the original design. The lower limit of compliance index is 1.0.
- For GLBTAVE, GLBTVAR, and GLBTEMP the default for ATTC is the grid point set identification number. Only grid points whose identification numbers appear on this SET command will be used.