Minimizing contact pressure

Another special usage of SIMULIA Tosca Structure.shape controller algorithm is the optimization of contact zones. Here it is important to understand that the normal shape optimization must be reversed because growth in a contact zones will result in a higher contact pressure and shrinkage in a lower. This is done by changing the setting SCALE in OPT_PARAM to a negative value, usually a small negative value e.g. -0.001.

This task shows you how to:

Before you begin:

The SIMULIA Tosca Structure.shape optimization of contact zones only works within the contact zone where small changes in the contact surface usually has a big influence on the contact pressure. This is the reason for a small SCALE value.

The CONTACT_PRESSURE design responses are currently only supported by Abaqus.

Optimize contact zones in Tosca ANSA® environment

  1. In OBJFUNC_TERM dialog, choose TYPE = SIG_CONTACT_PRESSURE:

  2. Choose SHAPE_OPTIMIZATION_CONTROLLER item and select New > SETTINGS.

  3. In the OPT_PARAM dialog, change the SCALE parameter:

Optimize contact zones inTosca Structure.gui

  1. Choose Command > DRESP.

    The DRESP menu appears.

  2. Define the SIG_CONTACT_PRESSURE as design response as shown in the following figure:

  3. Define the Optimization Parameters in the OPT_PARAM dialog as shown in the following figure:

SIMULIA Tosca Structure Parameter File

  • The resulting command in the parameter file look like follows: 

    DRESP
 ID_NAME        = MY_DRESP
 DEF_TYPE       = SYSTEM
 TYPE           = SIG_CONTACT_PRESSURE
 ND_GROUP       = DESIGN_NODES
 LC_SET         = ALL,1,All
 GROUP_OPER     = Max
END_
OPT_PARAM
 ID_NAME        = MY_PARAMETERS
 OPTIMIZE       = MY_OPTIMIZATION_TASK
 SCALE          = -0.001
END_