Reaction and Internal Heat Flux


Parameter Name	Formula
INTERNAL_HFLUX	$\sum_{e} \sum_{n} Q_{e,n} - q$
REACTION_HFLUX	$q$

with $q$ as the thermal reaction load at the boundary where the prescribed temperature is applied and $Q_{e, n}$ the internal load at the element e and DOF n.

Analysis Types: Thermal Analysis

The reaction fluxes and internal fluxes can be used to gain precise control over thermal optimization results. Reaction flux will occur at boundary regions where the temperature is prescribed. This is analogous to the reaction force in structural optimization. Internal flux must be specified using a specific element and degree of freedom. This is analogous to internal force response in structural optimization.

The following table shows the allowed combinations between strategy and the items OBJ_FUNC and CONSTRAINT with C for controller-based optimization and S for sensitivity-based optimization.


	TOPO	SHAPE	BEAD	SIZING
OBJ_FUNC	S
CONSTRAINT	S

Remarks

Only nodes of the node group (ND_GROUP) will be applied in the calculation of the reaction and internal heat flux.

Definition

The design responses (DRESP) for REACTION_HFLUX and INTERNAL_HFLUX are defined like:


DRESP
 ID_NAME  = DRESP_REACTION_HFLUX
 DEF_TYPE = SYSTEM
 TYPE     = REACTION_HFLUX
 ND_GROUP = node_group
END_

DRESP
 ID_NAME  = DRESP_INTERNAL_HFLUX
 DEF_TYPE = SYSTEM
 TYPE     = INTERNAL_HFLUX
 ND_GROUP = node_group
 EL_GROUP = element_group
END_