User-Defined Heat Transfer Properties

The LOADLIB I/O Option Entry, can be used in combination with:

The QVOL and QVOLLIB Bulk Data Entries for the definition of time-dependent and temperature-dependent volumetric heat generation through user-defined external functions, and/or,
The PCONV and PCONVLIB Bulk Data Entries for the definition of time-dependent and temperature-dependent free-convection coefficient through user-defined external functions.
The QBDY1 and QBDYLIB Bulk Data Entries for the definition of time-dependent and temperature-dependent uniform heat flux through user-defined external functions.
The SPCD and SPCDLIB Bulk Data Entries for the definition of time-dependent and temperature-dependent uniform heat flux through user-defined external functions.

The external functions may be written in Fortran or C. The resulting libraries and files should be accessible by OptiStruct regardless of the coding language, provided that consistent function prototyping is respected, and adequate compiling and linking options are used.

Write External Functions

Two Fortran subroutines are available, one is to define user-defined volumetric heat addition and the second is to define user-defined free convection coefficient.

Volumetric Heat Addition Subroutine

subroutine USRQVOL(ldsid,elabl,elset,nsetl,nsets,max_elset_len,
temp,max_temp_len,time,dtime,tbllabel,tblxy,tbllen,max_table_len,
ntables,evol,ethick,ecentroid, qheat,itablest,jtablest,rtablest,idtablest,
itables1,rtables1,ntables1,ltables1,ntablest,ltablest,itablemd, 
rtablemd,nitablemd,ntablemd,ltablemd)

Table 1 briefly describes the arguments which are passed among OptiStruct and the external subroutines.

Table 1. Subroutine Arguments
Argument	Type	Input/Output	Description
`ldsid`	Integer	Input	This is the user-defined `QVOL` Load Set identification number (User ID).
`elabl`	Character, vector	Input	`elabl` is the label of the `elset` (the identifier). It indicates the HyperMesh component name.
`elset`	Integer, vector	Input	The element ID’s in `elabl`. Internal IDs and then user-defined IDs following them (only for debugging purpose).
`nsetl`	Integer, vector	Input	Actual length of each `elset`
`nsets`	Integer, vector	Input	Total number of `elset`
`max_elset_len`	Integer, vector	Input	Maximum length of all the `elset`
`temp`	Double, vector	Input	Temperature calculated at the element centroid. This is based on internal IDs.
`time`	Double, scalar	Input	Current time
`dtime`	Double, scalar	Input	Time step
`tbllabel`	Character, vector	Input	Label of the TABLEG table
`tblxy`	Double, vector	Input	Contains the TABLEG X-Y values
`tbllen`	Integer, vector	Input	Actual length of each TABLEG table
`max_table_len`	Integer, vector	Input	Maximum length of all the TABLEG tables
`ntables`	Integer, vector	Input	Total number of TABLEG tables
`evol`	Double, vector	Input	Element volumes
`ethick`	Double, vector	Input	Element thicknesses
`ecentroid`	Double, vector	Input	Element centroid XYZ coordinates
`qheat`	Double, vector	Output	`q` calculated at the element centroid – the volume is calculated within the main source code of OptiStruct. `qheat` is vector, it will contain the `q`’s of all heated elements.
`itablest`	Integer, vector	Input	TABLEST integer data
`itablest(1)`	Integer	Input	Table identification number
`itablest(3)`	Integer	Input	Starting index of `jtablest`
`itablest(4)`	Integer	Input	Ending index of `jtablest`
`jtablest`	Integer, vector	Input	Contains the indexes for the TABLEST temperature values and TABLES1 entries.
`rtablest`	Double, vector	Input	TABLEST temperature values
`idtablest`	Integer, vector	Input	TABLEST and TABLES1 entries
`itables1`	Integer, vector	Input	TABLES1 integer data
`itables1(1)`	Integer	Input	Table identification number
`itables1(3)`	Integer	Input	Starting index of `rtables1`
`itables1(4)`	Integer	Input	Ending index of `rtables1`
`rtables1`	Double, vector	Input	TABLES1 X-Y values
`ntablest`	Integer, vector	Input	Total number of TABLEST tables
`ltablest`	Integer, vector	Input	Total length of each TABLEST table
`ntables1`	Integer, vector	Input	Total number of TABLES1 tables
`ltables1`	Integer, vector	Input	Total length of each TABLES1 table
`itablemd`	Integer, vector	Input	TABLEMD Integer data
`rtablemd`	Integer, vector	Input	TABLEMD X-Y values
`nitablemd`	Integer, scalar	Input	Total length of each TABLEMD table
`ntablemd`	Integer, scalar	Input	Total number of each TABLEMD table
`ltablemd`	Integer, scalar	Input	Total length of each RTABLEMD table

Free-Convection Coefficient Subroutine

subroutine 
USERHTC(pconvid,pconlabel,num_pconvlabels,cnvlabl,cnvset,cnvnsetl,
cnvnsets,max_cnvset_len,sidtemp,max_sidtemp_len,time,dtime,tbllabel,
tblxy,tbllen,max_table_len,ntables,xyzcoord,qvol_temperatures,
qvol_element_sets,qvol_element_sets_len,qvol_labels,num_qvol_labels,
max_qvol_sets_len,max_qvol_temp_len,htc,itablest,jtablest,rtablest,idtablest,
itables1,rtables1,ntables1,ltables1,ntablest,ltablest,itablemd,rtablemd,nitablemd,
ntablemd,ltablemd)

Table 2 briefly describes the arguments which are passed among OptiStruct and the external subroutines.

Table 2. Subroutine Arguments
Argument	Type	Input/Output	Description
`pconvid`	Integer	Input	Convection property identification number
`pconlabel`	Character	Input	Convection property identification label. This is the HyperMath property name.
`num_pconvlabels`	Integer, vector	Input	Number of `pconlabels`.
`cnvlabl`	Character, vector	Input	Label of the `cnvset` (the identifier). This is the HyperMath component name.
`cnvset`	Integer, vector	Input	Element ID’s and their side in `cnvlabl`. Internal element IDs defined on the CONV entry and then user element IDs to follow.
`cnvnsetl`	Integer, vector	Input	Actual length of each `cnvset`
`cnvnsets`	Integer, vector	Input	Total number of `cnvset`
`max_cnvset_len`	Integer, vector	Input	Maximum length of all the `cnvset`
`sidtemp`	Double, vector	Input	Temperature calculated at the element side centroid
`time`	Double, scalar	Input	Current time
`dtime`	Double, scalar	Input	Time step
`tbllabel`	Character, vector	Input	Label of the TABLEG table
`tblxy`	Double, vector	Input	Contains the TABLEG table X-Y values
`tbllen`	Integer, vector	Input	Actual length of each TABLEG table
`max_table_len`	Integer, vector	Input	Maximum length of all the TABLEG tables
`ntables`	Integer, vector	Input	Total number of TABLEG tables
`xyzcoord`	Double, vector	Input	Element’s side centroid nodal co-ordinates
`qvol_temperatures`	Integer, vector	Input	Temperatures calculated at the element centroid associated with a QVOL Bulk Data Entry.
`qvol_element_sets`	Integer, vector	Input	Element IDs in QVOL labels
`qvol_element_sets_len`	Character, vector	Input	Actual length of each QVOL element set
`qvol_labels`	Integer, vector	Input	Label of the QVOL element set
`num_qvol_labels`	Character, vector	Input	Total number of QVOL labels
`max_qvol_sets_len`	Integer, vector	Input	Maximum length of all QVOL element sets
`max_qvol_temp_len`	Integer, vector	Input	Maximum length of all QVOL temperatures
`htc`	Double, vector	Output	Convection Heat Transfer Coefficient calculated at the side centroid
`itablest`	Integer, vector	Input	TABLEST integer data
`itablest(1)`	Integer	Input	Table identification number
`itablest(3)`	Integer	Input	Starting index of `jtablest`
`itablest(4)`	Integer	Input	Ending index of `jtablest`
`jtablest`	Integer, vector	Input	Contains the indexes for the TABLEST temperature values and TABLES1 entries.
`rtablest`	Double, vector	Input	TABLEST temperature values
`idtablest`	Integer, vector	Input	TABLEST and TABLES1 entries
`itables1`	Integer, vector	Input	TABLES1 integer data
`itables1(1)`	Integer	Input	Table identification number
`itables1(3)`	Integer	Input	Starting index of `rtables1`
`itables1(4)`	Integer	Input	Ending index of `rtables1`
`rtables1`	Double, vector	Input	TABLES1 X-Y values
`ntablest`	Integer, vector	Input	Total number of TABLEST tables
`ltablest`	Integer, vector	Input	Total length of each TABLEST table
`ntables1`	Integer, vector	Input	Total number of TABLES1 tables
`ltables1`	Integer, vector	Input	Total length of each TABLES1 table

Heat Flux Subroutine

subroutine 
USERQBDY1(ldsid,elabl,elset,nsetl,nsets,max_elset_len,temp,max_temp_len,
time,dtime,tbllabel,tblxy,tbllen,max_table_len,ntables,areas,thicknesses,
xyzcoords,qbdy1,itablest,jtablest,rtablest,idtablest,itables1,rtables1,
ntables1,ltables1,ntablest,ltablest,itablemd,rtablemd,nitablemd,ntablemd,
ltablemd)

Table 3 briefly describes the arguments which are passed among OptiStruct and the external subroutines.

Table 3. Subroutine Arguments
Argument	Type	Input/Output	Description
`ldsid`	Integer	Input	This is the user-defined QBDY1 Load Set Identification number (User ID).
`elabl`	Character, vector	Input	`elabl` is the label of the `elset` (the identifier). It indicates the HyperMesh component name.
`elset`	Integer, vector	Input	The element ID’s in `elabl`. Internal IDs and then user-defined IDs following them (only for debugging purpose).
`nsetl`	Integer, vector	Input	Actual length of each `elset`
`nsets`	Integer, vector	Input	Total number of `elset`
`max_elset_len`	Integer, vector	Input	Maximum length of all the `elset`
`temp`	Double, vector	Input	Temperature calculated at the element centroid. This is based on internal IDs.
`time`	Double, scalar	Input	Current time
`dtime`	Double, scalar	Input	Time step
`tbllabel`	Character, vector	Input	Label of the TABLEG table
`tblxy`	Double, vector	Input	Contains the TABLEG table X-Y values
`tbllen`	Integer, vector	Input	Actual length of each TABLEG table
`max_table_len`	Integer, vector	Input	Maximum length of all the TABLEG tables
`ntables`	Integer, vector	Input	Total number of TABLEG tables
`areas`	Double, vector	Input	Element area
`thicknesses`	Double, vector	Input	Element thicknesses
`xyzcoords`	Double, vector	Input	Element centroid nodal coordinates.
`qbdy1`	Double, vector	Output	`q` calculated at the element centroid `-qbdy1` is a vector, it will contain the `q`’s of all heated elements.
`itablest`	Integer, vector	Input	TABLEST integer data
`itablest(1)`	Integer	Input	Table identification number
`itablest(3)`	Integer	Input	Starting index of `jtablest`
`itablest(4)`	Integer	Input	Ending index of `jtablest`
`jtablest`	Integer, vector	Input	Contains the indexes for the TABLEST temperature values and TABLES1 entries
`rtablest`	Double, vector	Input	TABLEST temperature values
`idtablest`	Integer, vector	Input	The TABLEST and TABLES1 entries
`itables1`	Integer, vector	Input	The TABLES1 integer data
`itables1(1)`	Integer	Input	Table identification number
`itables1(3)`	Integer	Input	Starting index of `rtables1`
`itables1(4)`	Integer	Input	Ending index of `rtables1`
`rtables1`	Double, vector	Input	TABLES1 X-Y values
`ntablest`	Integer, vector	Input	Total number of TABLEST tables
`ltablest`	Integer, vector	Input	Total length of each TABLEST table
`ntables1`	Integer, vector	Input	Total number of TABLES1 tables
`ltables1`	Integer, vector	Input	Total length of each TABLES1 table
`itablemd`	Integer, vector	Input	TABLEMD Integer data
`rtablemd`	Double, vector	Input	TABLEMD X-Y values
`nitablemd`	Integer, scalar	Input	Total length of each TABLEMD table
`ntablemd`	Integer, scalar	Input	Total number of TABLEMD tables
`ltablemd`	Integer, scalar	Input	Total length of each RTABLEMD table

SPCD Temperature Subroutine

subroutine 
USERSENSOR(ldsid,nlabl,ndset,ndsetl,cntrlset,cntrlsetl,ndsets,max_ndset_len,
max_cntrlset_len,tempn,max_tempn_len,max_tempinf_len,time,dtime,tbllabel,tblxy,
tbllen,max_table_len,ntables,tempinf,itablest,jtablest,rtablest,idtablest,itables1,
rtables1,ntables1,ltables1,ntablest,ltablest,itablemd,rtablemd,nitablemd,ntablemd,
ltablemd)

Table 4 briefly describes the arguments which are passed among OptiStruct and the external subroutines.

Table 4. Subroutine Arguments
Argument	Type	Input/Output	Description
`ldsid`	Integer	Input	SPCD load set ID (user-defined SPCD ID)
`nlabl`	Character, Vector	Input	Label of the NDSET (identifier). This is the HyperMesh node SET label (for ambient node).
`ndset`	Integer, vector	Input	Node ID’s in `nlabl`. It contains the internal IDs and then user-defined IDs follow.
`ndsetl`	Integer, vector	Input	Actual length of each `ndset`
`ndsets`	Integer, vector	Input	Total number of `ndset`
`max_ndset_len`	Integer, vector	Input	Maximum length of all the `ndset`
`cntrlset`	Integer, vector	Input	Control node IDs. These are internal IDs and then user-defined IDs to follow.
`cntrlsetl`	Integer, vector	Input	Actual length of each `cntrlset`.
`cntrlsets`	Integer, vector	Input	Total number of `cntrlset`.
`max_cntrlset_len`	Integer, vector	Input	Maximum length of all the `cntrlset`
`tempn`	Double, vector	Input	Calculated nodal temperature.
`tempinf`	Double, vector	Output	Ambient Temperatures at the control nodes.
`time`	Double, scalar	Input	Current time
`dtime`	Double, scalar	Input	Time step
`tbllabel`	Character, vector	Input	Label of the TABLEG table
`tblxy`	Double, vector	Input	Contains the TABLEG table X-Y values
`tbllen`	Integer, vector	Input	Actual length of each TABLEG table
`max_table_len`	Integer, vector	Input	Maximum length of all the TABLEG tables
`ntables`	Integer, vector	Input	Total number of TABLEG tables
`itablest`	Integer, vector	Input	TABLEST Integer data
`itablest(1)`	Integer	Input	Table identification number
`itablest(3)`	Integer	Input	Starting index of `jtablest`
`itablest(4)`	Integer	Input	Ending index of `jtablest`
`jtablest`	Integer, vector	Input	Contains the indexes for the TABLEST temperature values and TABLES1 entries
`rtablest`	Double, vector	Input	TABLEST temperature values
`idtablest`	Integer, vector	Input	The TABLEST and TABLES1 entries
`itables1`	Integer, vector	Input	The TABLES1 integer data
`itables1(1)`	Integer	Input	Table identification number
`itables1(3)`	Integer	Input	Starting index of `rtables1`
`itables1(4)`	Integer	Input	Ending index of `rtables1`
`rtables1`	Double, vector	Input	TABLES1 X-Y values
`ntablest`	Integer, vector	Input	Total number of TABLEST tables
`ltablest`	Integer, vector	Input	Total length of each TABLEST table
`ntables1`	Integer, vector	Input	Total number of TABLES1 tables
`ltables1`	Integer, vector	Input	Total length of each TABLES1 table
`itablemd`	Integer, vector	Input	TABLEMD integer data.
`rtablemd`	Double, vector	Input	TABLEMD X-Y values
`nitablemd`	Integer, scalar	Input	Total length of each TABLEMD table.
`ntablemd`	Integer, scalar	Input	Total number of TABLEMD tables.
`ltablemd`	Integer, scalar	Input	Total length of each RTABLEMD table.

Build External Libraries for User-Defined Materials

You can build shared libraries on Windows or Linux. Refer to Build External Libraries for more information.