Space Radiation Specification
Description: Specifies a
CHBDYi element face for application of radiation boundary conditions.
Format:
Example:
Alternate Format and Example:
Field
|
Definition
|
Type
|
Default
|
AMBND
|
Ambient point for radiation exchange.
|
Integer > 0
|
Required
|
FAMB
|
Radiation view factor between the face and the ambient point.
|
Real ≥ 0.0
|
Required
|
CNTRLND
|
Control point for free convection boundary condition.
|
Integer ≥ 0 or blank
|
0
|
EIDi
|
CHBDYi element identification number(s).
|
Integer > 0; EID2 > EID1
|
Required
|
INC
|
Element number increment.
|
Integer or blank
|
1
|
Remarks:
- The basic exchange relationship can be expressed in one of the following forms:
- , CNTRLND ≠ 0
- , CNTRLND = 0
- AMBND is treated as a black body with its own ambient temperature for radiation exchange between the surface element and space.
- Two PARAM entries are required for radiation heat transfer:
- TABS defines the absolute temperature scale factor used to convert temperature to absolute. (See Section 5,
Parameters, for more information on
TABS.)
- SIGMA () is the Stefan-Boltzmann constant. (See Section 5,
Parameters, for more information on
SIGMA.)
- At least one EID must be present on each
QVOL entry.
- If the alternate form is used, all elements EID1 through EID2 that are not compatible or do not exist will be skipped.
- Elements must not be specified more than once.
- All elements directly referenced must exist.
- The continuations are not allowed.