3.2 2D Elements

3.2.1 Tr1ht element

Implements the linear triangular finite element for heat transfer problems. Each node has 1 degree of freedom. The cross section thickness property is requested form cross section model. The node numbering is anti-clockwise. The element features are summarized in Table 57.


PIC

Figure 27: Tr1ht element - node and side numbering.





Keyword

Tr1ht

Description

triangular finite element with linear approximation for heat transfer problems

Specific parameters

-



Unknowns

Single dof (T_f - temperature) is required in each node.

Approximation

Linear approximation of temperature.

Integration

Integration using one point gauss integration formula.

Loads

Body loads are supported. Boundary loads are supported and are computed using numerical integration. The side numbering is following. Each i-th element side begins in i-th element node and ends on next element node (i+1-th node or 1-st node, in the case of side number 3). The local positive edge x-axis coincides with side direction, the positive local edge y-axis is rotated 90 degrees anti-clockwise (see fig. (27)).

Features

-

CS properties

-

Status

Tests/Examples

tests/tm/tmpatch43-1.in, tests/tm/tmpatch43-2.in, tests/tm/tmpatch43-3.in, tests/tm/tmpatch45-1.in




Table 57: Tr1ht element summary

3.2.2 Tr1mt element

Isoparametric triangular finite element with linear approximation of moisture. Other features are the same as for Tr1ht in Section 3.2.1.

3.2.3 Tr1hmt element

Isoparametric triangular finite element with linear approximations of temperature and moisture. Other features are the same as for Tr1ht in Section 3.2.1.

Tests/Examples: tests/tm/HeMoKunzel_1.in

3.2.4 Quad1ht element

Represents isoparametric four-node quadrilateral finite element for heat transfer problems. Each node has 1 degree of freedom. Problem should be defined in x,y plane. The cross section thickness property is requested form cross section model. The nodes should be numbered anti-clockwise (positive rotation around z-axis). The element features are summarized in Table 58.


PIC

Figure 28: Quad1ht element. Node numbering, Side numbering and definition of local edge c.s.(a).





Keyword

Quad1ht

Description

Isoparametric four-node quadrilateral linear interpolation element for heat transfer problems

Specific parameters

[NIP #(in)]



Parameters

NIP: allows to change the default number of integration point used.

Unknowns

Single dof (T_f - temperature) is required in each node.

Approximation

Linear approximation of temperature.

Integration

Integration using gauss integration formula in 4 (the default), 9, or 16 integration points. The default number of integration point used can be overloaded using NIP parameter.

Loads

Body loads are supported. Boundary loads are supported and computed using numerical integration. The side numbering is following. Each i-th element side begins in i-th element node and ends on next element node (i+1-th node or 1-st node, in the case of side number 4). The local positive edge x-axis coincides with side direction, the positive local edge y-axis is rotated 90 degrees anti-clockwise (see fig. (28)).

Features

-

CS properties

-

Status

Tests/Examples

tests/tm/tmpatch01.in, tests/tm/tmpatch02.in, tests/tm/tmpatch03.in, tests/tm/tmpatch04.in




Table 58: Quad1ht element summary

3.2.5 Quad1mt element

Isoparametric four-node quadrilateral finite element. Other features are the same as for Quad1ht in Section 3.2.4.

Tests/Examples: tests/tm/nlisomoisture01.in, tests/tm/nlisomoisture02.in

3.2.6 Quad1hmt element

Represents isoparametric four-node quadrilateral finite element for heat and mass (one constituent) transport problems. Two dofs (T_f - temperature and C_1 - concentration) are required in each node. Linear approximation of temperature and mass concentration. Other features are similar to Quad1 element, see section 3.2.4.

3.2.7 QQuad1ht element

Represents isoparametric quadratic eight-node quadrilateral finite element for heat transfer problems. Each node has 1 degree of freedom. Problem should be defined in x,y plane. The cross section thickness property is requested form the cross section model. The nodes should be numbered anti-clockwise (positive rotation around z-axis), see fig. 10. The element has the same features as in Table 58.

Tests/Examples: tests/tm/qquad01.in

3.2.8 QQuad1mt element

Element for mass transport problems, see the parent element in sec. 3.2.7.

3.2.9 QQuad1hmt element

Element for heat and mass transport problems, see the parent element in sec. 3.2.7.