Keyword type: model definition, surface interaction
With this option the surface behavior of a surface interaction can be defined. The surface behavior is required for any contact analysis. There is one required parameter PRESSURE-OVERCLOSURE. It can take the value EXPONENTIAL or LINEAR.
The exponential pressure-overclosure behavior takes the form in Figure
105. The parameters and
define the kind of
contact.
is the contact pressure at zero distance,
is the distance from
the master surface at which the pressure is decreased to 1 % of
. The
behavior in between is exponential. A large value of
leads to soft
contact, a small value to hard contact.
The linear pressure-overclosure behavior (Figure 106) simulates a linear relationship between the pressure and the overclosure. At zero overclosure the pressure is zero as well. The user has to specify the slope of the pressure-overclosure curve and can specify a tension value for large clearances (should be small).
First line:
Following line if PRESSURE-OVERCLOSURE=EXPONENTIAL:
Following line if PRESSURE-OVERCLOSURE=LINEAR:
Example: *SURFACE BEHAVIOR,PRESSURE-OVERCLOSURE=EXPONENTIAL 1.e-4,.1
defines a distance of length units at which the contact pressure is
.001 pressure units, whereas the contact pressure at loose contact is 0.1
pressure units.
Example files: contact1, contact2.