Minimizing the maximum equivalent stress

Probably the most used shape optimization type is a minimization of the maximal von Mises stresses. This task is automated in SIMULIA Tosca Structure so that the user must not care about any reference values.

This task shows you how to:

Before you begin:

If the default settings cause the geometry to change unwanted in size a volume constraint can be utilized.

Minimize the maximum equivalent stress in Tosca ANSA® environment

  1. Select OBJ_FUNC.

  2. Apply New > EQUIVALENT_STRESS as shown in the following figure:

  3. Click OK.

  4. Select OBJ_FUNC > Edit.

  5. Set TARGET = MINMAX.

Minimize the maximum equivalent stress in Tosca Structure.gui

  1. Choose Command > DRESP.

    The DRESP menu appears.

  2. Set Type = SIG_MISES as shown in the following figure:

  3. Choose Command > OBJ_FUNC.

    The OBJ_FUNC menu appears.

  4. Select Target= MinMax.

  5. Set RefValue to 120.

SIMULIA Tosca Structure Parameter File

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

    DRESP
 ID_NAME        = DRESP_VON_MISES
 DEF_TYPE       = SYSTEM
 TYPE           = SIG_MISES
 ND_GROUP       = design_nodes
 LC_SET         = ALL,1,All
 LC_SET         = ALL,2,All
 GROUP_OPER     = Max
END_
OBJ_FUNC
 ID_NAME        = MY_OBJ_FUNC
 TARGET         = MINMAX
 DRESP          = DRESP_VON_MISES, ,  
END_