FEA DesignVariableRelation

Structure for the design variable tuple = ("DesignVariableRelation Name", "Value"). "DesignVariableRelation Name" defines the reference name for the design variable being specified. This string will be used in the FEA input directly. The "Value" must be a JSON String dictionary (see Section JSON String Dictionary).

JSON String Dictionary

If "Value" is JSON string dictionary (eg. "Value" = {"componentType": "Property", "componentName": "plate", "fieldName": "TM", "variableName": "MyDesVar"}) the following keywords ( = default values) may be used:

• componentType = "Property"
  The type of component for this design variable relation. Options: "Material", "Property", "Element".

• componentName = "(no default)"
  Single or list of FEA Property(ies), or FEA Material name(s) linked to the design variable relation (e.g. "Name1" or ["Name1","Name2",...].
  • For componentType Property a FEA Property name (or names) is given.
  • For componentType Material a FEA Material name (or names) is given.
  • For componentType Element a capsGroup Name (or names) is given.

• variableName = "(no default)"
  Single or list of names of design variables linked to this relation

• fieldName = "(no default)"
  Fieldname of variable relation (e.g. "E" for Young's Modulus). Design Variable Relations can be defined as three types based on the variableType value. These are Material, Property, or Element. This means that an aspect of a material, property, or element input can change in the optimization problem. This input specifies what aspect of the Material, Property, or Element is changing.
  1. Material Types Selected based on the material type (see FEA Material, materialType) referenced in the componentName above.
     • MAT1, materialType = "Isotropic"
       • "E", "G", "NU", "RHO", "A"
     • MAT2, materialType = "Anisothotropic"
       • "G11", "G12", "G13", "G22", "G23", "G33", "RHO", "A1", "A2", "A3"
     • MAT8, materialType = "Orthotropic"
       • "E1", "E2", "NU12", "G12", "G1Z", "G2Z", "RHO", "A1", "A2"
     • MAT9, materialType = "Anisotropic"
       • "G11", "G12", "G13", "G14", "G15", "G16"
       • "G22", "G23", "G24", "G25", "G26"
       • "G33", "G34", "G35", "G36"
       • "G44", "G45", "G46"
       • "G55", "G56", "G66"
       • "RHO", "A1", "A2", "A3", "A4", "A5", "A6"
  2. Property Types (see FEA Property)
     • PROD propertyType = "Rod"
       • "A", "J"
     • PBAR propertyType = "Bar"
       • "A", "I1", "I2", "J"
     • PSHELL propertyType = "Shell"
       • "T"
     • PCOMP propertyType = "Composite"
       • "T1", "THETA1", "T2", "THETA2", ... "Ti", "THETAi"
     • PSOLID propertyType = "Solid"
       • not supported
  3. Element Types
     • CTRIA3, CQUAD4 propertyType = "Shell"
       • "ZOFFS"

• fieldPosition = 0
  This input is ignored if not defined. The user may use this field instead of the fieldName input defined above to relate design variables and property, material, or elements. This requires knowledge of Nastran bulk data input format for material, property, and element input cards.

• constantCoeff = 0.0
  Constant term of relation.

• linearCoeff = 1.0
  Single or list of coefficients of linear relation. Must be same length as variableName.