INTER193


2D 6-Node Gasket

Valid Products: Pro | Premium | Enterprise | PrepPost | Solver | AS add-on

INTER193 Element Description

INTER193 is a 2D 6-node quadratic interface element used for 2D structural assembly modeling. When used in conjunction with 2D quadratic structural elements (such as PLANE183), INTER193 is used to simulate gasket joints. The element can be used either as a plane element (plane stress or plane strain) or as an axisymmetric element. It is defined by six nodes having two degrees of freedom at each node: translations in the nodal x and y directions.

See Gasket Material and INTER193 in the Mechanical APDL Theory Reference for more details about this element.

Also see Gasket Joints Simulation in the Structural Analysis Guide for more details on the gasket capability in Mechanical APDL.

Figure 193.1: INTER193 Geometry

INTER193 Geometry

INTER193 Input Data

The element geometry, node locations, connectivity, and the nodal coordinate system are shown in Figure 193.1: INTER193 Geometry. The element geometry is defined by 6 nodes, which form bottom and top lines of the element. The bottom line is defined by nodes I, J, M; and the top line is defined by nodes K, L, O. The element connectivity is defined as I, J, K, L, M, O. This element has 2 integration points. Dropping mid side nodes M or O is not permitted.

Temperatures may be input as element body loads at the nodes. The node I temperature T(I), defaults to TUNIF. If all other temperatures are unspecified, they default to T(I). For any other input pattern, unspecified temperatures default to TUNIF.

Input the nodal forces, if any, per unit of depth for a plane analysis (except for KEYOPT(3) = 3) and on a full 360° basis for an axisymmetric analysis.

By default, the element adopts a full-integration scheme (KEYOPT(4) = 2), and is capable of both through-thickness and transverse shear deformations (KEYOPT(2) = 1). The full-integration scheme and the inclusion of transverse shear stiffness are generally required when the interfaces between the gasket and the mating parts are modeled as sliding contact. However, if the interfaces are modeled with a matching mesh method (that is, with coincident nodes), Ansys, Inc. recommends using the reduced integration scheme (KEYOPT(4) = 0) and through-thickness deformation only (KEYOPT(2) = 0) to achieve better efficiency and to avoid unnecessary in-plane interaction between the gasket and the mating parts.

The next table summarizes the element input. See Element Input in the Element Reference for a general description of element input.

INTER193 Input Summary

Nodes

I, J, K, L, M, , O

Degrees of Freedom

UX, UY

Real Constants
None, if KEYOPT(3) = 0, 1, or 2
THK - Plane stress with thickness, if KEYOPT(3) = 3
Material Properties

TB command: Gasket material

MP command: BETD, ALPX (or CTEX or THSX), DMPR, DMPS

Body Loads
Temperatures -- 

T(I), T(J), T(K), T(L), T(M), T(O)

Special Features
KEYOPT(2)

Element deformation:

0  -- 

Through-thickness deformation only

1 -- 

Through-thickness and transverse shear deformation (default)

KEYOPT(3)

Element behavior:

0  -- 

Plane stress

1 -- 

Axisymmetric

2 -- 

Plane strain (Z strain = 0.0)

3 -- 

Plane stress with thickness (THK) real constant input

KEYOPT(4)

Element technology:

0  -- 

Uniform reduced integration

2 -- 

Full integration (default)

KEYOPT(8)

Element component quantity output:

0  -- 

Gasket quantities are output (GKD, GKD, GKI, and GKTH) (default)

1 -- 

Standard stresses and strains are output (including S, EPEL, and EPTH )

INTER193 Output Data

The solution output associated with the element is in two forms:

The output directions for element items are parallel to the local element coordinate system based on the element midplane as illustrated in Figure 193.2: INTER193 Stress Output. See Gasket Material in the Mechanical APDL Theory Reference for details.

A general description of solution output is given in Solution Output. See the Basic Analysis Guide for ways to review results.

Figure 193.2: INTER193 Stress Output

INTER193 Stress Output

The Element Output Definitions table uses the following notation:

A colon (:) in the Name column indicates that the item can be accessed by the Component Name method (ESOL). The O column indicates the availability of the items in the file Jobname.out. The R column indicates the availability of the items in the results file.

In either the O or R columns, “Y” indicates that the item is always available, a number refers to a table footnote that describes when the item is conditionally available, and “-” indicates that the item is not available.

Table 193.1: INTER193 Element Output Definitions

NameDefinitionOR
ELElement number-Y
NODESNode connectivity - I, J, K, L, M, O-Y
MATMaterial number-Y
TEMPTemperatures T(I), T(J), T(K), T(L), T(M), T(O)-Y
GKS:X, (XY)

X - Normal stress (also gasket pressure)

XY - Transverse shear stress

YY
GKD:X, (XY)

X - Total closure

XY - Relative transverse shear deformation (, where is the transverse shear strain, and is the gasket thickness.

YY
GKDI:X, (XY)Total inelastic closureYY
GKTH:X, (XY)Thermal closureYY
S:X, Y, Z, XYStresses (SZ = 0.0 for plane stress elements) -1
S:INTStress intensity -1
S:EQVEquivalent stress -1
EPEL:X, Y, Z, XYElastic strains -1
EPEL:EQVEquivalent elastic strain -1
EPTH:X, Y, Z, XYThermal strains -1
EPTH:EQVEquivalent thermal strain -1
SEND:ELASTICStrain energy densities-1

  1. To save these results to the .rst file, set KEYOPT(8) = 1.

INTER193 Assumptions and Restrictions

  • This element is not supported for initial stress.

  • Pressure as a type of surface load on element faces is not supported by this element.

  • This element is based on the local coordinate system; therefore, setting an element coordinate system attribute pointer (ESYS) is not supported.

INTER193 Product Restrictions

There are no product-specific restrictions for this element.