INTER194 Element Description

INTER194 is a 3-D 16-node quadratic interface element. When used with 3-D quadratic structural elements (SOLID96, SOLID186, and SOLID187), INTER194 simulates gasket joints. It is defined by 16 nodes having three degrees of freedom at each node: translations in the nodal x, y, and z directions.

See Gasket Material and INTER194 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 about gasket simulation.

Figure 194.1:  INTER194 Geometry

INTER194 Input Data

The element geometry, node locations, connectivity, and the nodal coordinate system are shown in Figure 194.1: INTER194 Geometry. The element geometry is defined by 16 nodes, which form bottom and top surfaces of the element. The bottom surface is defined by nodes, I, J, K, L, Q, R, S, T; and the top surface is defined by nodes, M, N, O, P, U, V, W, X. As shown, the element connectivity is defined as I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X. The element is degenerated to a wedge (prism) element, when K=L=S and O=P=W, as shown in Figure 194.2: INTER194 3-D 16-Node Degenerated Quadratic Interface.

Figure 194.2:  INTER194 3-D 16-Node Degenerated Quadratic Interface

For the degenerated element, 3 integration points are used for numerical integration. The degenerated element can be used in conjunction with 10-node solid tetrahedral elements (such as SOLID187). Dropping any or some of midside nodes, Q, R, S, T, U, V, W, X 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.

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.

You can define element orientation (ESYS) as described in Coordinate Systems:

Figure 194.3:  INTER94 Element Orientation

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

INTER194 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 194.4: INTER194 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 194.4:  INTER194 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.

INTER194 Assumptions and Restrictions

INTER194 Product Restrictions

There are no product-specific restrictions for this element.