1. Discretization

1.1. Degrees of freedom

The degrees of freedom are temperatures TEMP (temperature on the average surface of the shell), TEMP_INF (temperature on the lower surface of the shell), and TEMP_SUP (temperature on the upper surface of the shell).

1.2. Stiffness matrix support meshes

Modeling

Mesh

Finished Element

Remarks

COQUE	TRIA3	THCOTR3	3-coordinate nodes \(x\), \(y\), \(z\)
	TRIA6	THCOTR6
	TRIA7	THCOTR7
	QUAD4	THCOQU4
	QUAD8	THCOQU8
	QUAD9	THCOQU9
COQUE_PLAN	SEG3	THCPSE3	nodes with 2 coordinates \(x\), \(y\)
COQUE_AXIS	SEG3	THCASE3

For THCOTRi, only the 3 vertices are used to define the local geometry (tangential plane, normal). For THCOQUi, we consider that the element is plane and its tangential plane is defined by default by 3 of the 4 vertices of the element.

1.3. Cargo support mesh

All the loads applicable to the facets of the shell elements are treated by direct discretization on the support mesh of the element in temperature formulation.

No load support mesh is therefore necessary for the faces of the shell elements.

For the loads applicable on the edges of the shell or plate elements of the -shell- modeling, a SEG2 or SEG3 support mesh must be used.

Modeling

Mesh

Finished Element

Remarks

COQUE	SEG2	THCOSE2	with TRIA3et QUAD4
COQUE	SEG3	THCOSE3	with TRIA6ou TRIA7et QUAD8ou QUAD9

For the temperatures imposed, the support meshes are meshes reduced to one point.