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MANUALS:
  • Short Guide to INVERSE
  • Flow Control
  • Expression evaluator
  • User defined variables
  • General file interface
  • Syntax checker & debugger
  • Interfaces with simulation programmes
  • Elfen's Interface
    		•
    Manuals list Manuals list & contents Table of contents 

     
     
     
     
     

    Interfaces between the Optimisation Shell INVERSE

    and Simulation Programmes
     
     

    Version 0
     
     
     
     
     
     
     
     
     

    Igor Gresovnik
     
     

    Ljubljana, the 30 th of November 1998






     

    Table of contents:
     
     

    1. Shell-Simulation Interfaces *

    1.1 Elfen's Interface *  
    1.1.1 The expression evaluator's functions that return Elfen's result data from the output file *
     
    1. Shell-Simulation Interfaces


      1. Elfen's Interface

        2.  
        Manuals list Manuals list & contents Table of contents 

        Elfen is a general purpose finite element programme for solution of thermo-mechanical problems in solid mechanics. It is capable of solving nonlinear problems involving large strains and deformations, different material models, thermo-mechanical coupling and contact phenomena. It is therefore convenient for simulation of a large range of forming processes or product behavior in operating conditions.

        At the current stage, a file interface between the shell Inverse and Elfen is available. The interfacing utilities include reading individual results or result fields from Elfen's output files, and replacing fields in the Elfen's input files. It is usually much more comfortable to use these interfacing utilities than to use the general file interface.

        A set of expression evaluator's functions that read individual results from the analysis output file is available. These functions can be used in mathematical expressions evaluated by the expression evaluator. This way, the analysis results can be grabbed and used at in the evaluation of the objective and constraint functions and their derivatives. An example is the expression evaluator's function noddisp that returns a specific component of specific nodal displacement after a specific increment.

        Before the appropriate expression evaluator's functions are used, the analysis result file must be connected with the pre-defined file variable anoutfile and the initoutput command must be executed.

        There is a set of file interpreter's functions that read whole fields from analysis result files and store them in field variables. These functions can be used when a lot of individual field components are involved in calculation of the functions derived from analysis result. Reading whole fields into field variables and then operating with components of these variables can in such cases be quicker than using expression evaluator's functions that return individual components of the result fields. Sometimes whole result fields are used as an input for another analysis. For example, at shape optimisation the parametrised mesh, which depends on optimisation (shape) parameters, is often obtained by elastic deformation of a reference mesh. The initial mesh at specific parameters is obtained by adding displacements from the elastic analysis to the reference mesh.
         
         

        1. The expression evaluator's functions that return Elfen's result data from the output file

         
          1. anerror [ ]

            2. Returns 1 if error at analysis occurred according to what is written in the analysis output file. Otherwise it returns 0.
             

          2. ansuccess [ ]

            3. Returns 1 if analysis has successfully completed according to what is written in the analysis output file. Otherwise it returns 0.
             

          3. nodcoord [node,coord]

            4. Returns the coordinate coord of the initial position of the node node.
             

          4. nodtemp [inc,nod,1]

            5. Returns the temperature of the node node nod after the increment inc. The third argument must be specified, even if it does not have any meaning. It is usually set to 1.
             

          5. noddisp [inc,nod,comp]

            6. Returns the component comp of the nodal displacement of the node nod after the increment inc.
             

          6. locnoddisp [inc,nod,comp]

            7. Returns the component comp of the nodal displacement of the node nod after the increment inc in the local coordinate system.
             

          7. nodreac [inc,nod,comp]

            8. Returns the component comp of the nodal reaction of the node nod after the increment inc.
             

          8. locnodreac [inc,nod,comp]

            9. Returns the component comp of the nodal reaction of the node nod after the increment inc in the local coordinate system.
             

          9. nodstrain [inc,nod,i,j]

            10. Returns the i,j-th component of the nodal strain in the node nod after the increment inc.
             

          10. nodstress [inc,nod,i,j]

            11. Returns the i,j-th component of the nodal stress in the node nod after the increment inc.
             

          11. nodcontforc [inc,nod,comp]

            12. Returns the component comp of the contact nodal force in the node nod after the increment inc.
             

          12. nodloccontforc [inc,nod,comp]

            13. Returns the component comp of the contact nodal force in the node nod after the increment inc in the local coordinate system.
             

          13. nodwear [inc,nod,comp]

            14. Returns specific parameters of wear in the node nod after the increment inc. The Stanislava Stupkiewicz's friction and wear model is used. comp specifies which data is to be returned.