Product: ABAQUS/Standard
User subroutine FILM:
can be used to define a node-based, element-based, or surface-based nonuniform film coefficient;
can be used to define sink temperatures as functions of position, time, temperature, node number, element number, integration point number, etc.;
will be called during procedures that allow heat transfer analysis at each node or surface integration point of those surfaces and elements for which node-based, element-based, or surface-based nonuniform film conditions are defined;
ignores any amplitude references for the sink temperature or film coefficient that may appear with the associated nonuniform film definition; and
uses the nodes for first-order heat transfer elements as surface integration points for both element-based and surface-based films.
SUBROUTINE FILM(H,SINK,TEMP,KSTEP,KINC,TIME,NOEL,NPT,
1 COORDS,JLTYP,FIELD,NFIELD,SNAME,NODE,AREA)
C
INCLUDE 'ABA_PARAM.INC'
C
DIMENSION H(2),TIME(2),COORDS(3), FIELD(NFIELD)
CHARACTER*80 SNAME
user coding to define H(1), H(2), and SINK
RETURN
ENDH(1)
Film coefficient at this point. Units are JT–1L–2
–1. H(1) will be passed into the routine as the magnitude of the film coefficient specified as part of the node-based, element-based, or surface-based film condition definition. If the magnitude is not defined, H(1) will be initialized to zero. This film coefficient is not available for output purposes.
H(2)
, rate of change of the film coefficient with respect to the surface temperature at this point. Units are JT–1L–2–2. The rate of convergence during the solution of the nonlinear equations in an increment is improved by defining this value, especially when the film coefficient is a strong function of surface temperature.
SINK
Sink temperature. SINK will be passed into the routine as the sink temperature specified as part of the node-based, element-based, or surface-based film condition definition. If the sink temperature is not defined, SINK will be initialized to zero. This sink temperature is not available for output purposes.
TEMP
Estimated surface temperature at this time at this point.
KSTEP
Step number.
KINC
Increment number.
TIME(1)
Current value of step time.
TIME(2)
Current value of total time.
NOEL
Element number. This variable is passed in as zero for node-based films.
NPT
Surface integration point number. This variable is passed in as zero for node-based films.
COORDS
An array containing the coordinates of this point. These are the current coordinates if geometric nonlinearity is accounted for during the step (see “Procedures: overview,” Section 6.1.1 of the ABAQUS Analysis User's Manual); otherwise, the array contains the original coordinates of the point.
JLTYP
Identifies the element face for which this call to FILM is being made for an element-based film coefficient specification. This information is useful when several different nonuniform film conditions are being imposed on an element at the same time. See Part VI, “Elements,” of the ABAQUS Analysis User's Manual for element face identification. The key is as follows:
FIELD
Interpolated values of field variables at this point.
NFIELD
Number of field variables.
SNAME
Surface name for which this call to FILM is being made for a surface-based film coefficient specification (JLTYP=0). This variable is passed in as blank for both node-based and element-based films.
NODE
Node number. This variable is passed in as zero for both element-based and surface-based films.
AREA
Nodal area for node-based films. AREA will be passed into the routine as the nodal area specified as part of the node-based film coefficient specification. This nodal area is not available for output purposes. This variable is passed in as zero for both element-based and surface-based films.