30 Replies Latest reply on Apr 2, 2014 3:45 PM by Jared Conway

    Nonlinear problem on Elastic couplings.

    Stefo Peev

      Hi, everyone. I have a problem with nonlinear simulation of elastic coupling. I want to simulate the deformation of the elastic element (rubber) with 80 Nm torque. Everytime I get a different error of the simulation. I was trying everything  to get done, but that simulation it pissing me off. Can anyone help me for that? Now I will write every option and settings, that I have given to the simulation.

       

      1. Nonlinear simulation study.

      2.Simulation properties.

           2.1. Autostepping.

                Initial time increment - 0.01;

                Min - 1e-008; Max - 0.1;

                No. of adjustments - 30.

           2.2 Geometry nonlinearity options.

                Use large displacement formulation.

           2.3. Solver.

                Direct Sparse.

           2.4. Incompatible bonding options.

                More accurate.

           2.5. Advanced Options.

                Control - Force;

                Iterative - NR;

                Integration - Newmark;

                Do equilibrium iteration every - 1 step;

                Maximum equilibrium iterations - 30;

                Convergence tolerance - 0.001;

                Maximum incremental strain - 0.01;

                Singularity elimination factor - 0.

      3. Material properties.

           3.1. Coupling - ANSI 1020.

           3.2. Elastic element - Rubber.

                Model Type: Hyperelastic - Mooney Rivlin;

                Poisson Ration - 0.4995;

                Thermal Expansion Coefficient - 0.00066 /K;

                First constant - 5.79 N/mm^2;

                Second constant - 1.45 N/mm^2;

                Mass Density - 1000 kg/m^3;

                Tensile Strenght - 13.79 N/mm^2.

          P.S. I was trying with Stress - Strain Curve, too.

      4. Connections.

           4.1. Component Contacts - Global Bonded Contact with Compatible Mesh.

           4.2. Contact Sets - No penetration (for all faces); Surface to Surface; Friction - 0.8.

          P.S. Contact face between eight cylindrical faces and thumbs of coupling is 100 mm^2.

      5. Fixes.

           5.1. Half of the coupling is fixed.

           5.2. On a bore of the other half of the coupling is set on Fixed Hinge.

      6. External Loads.

           6.1. On a bore of the same half of the coupling is set 80 Nm torque.

      7. Mesh.

           7.1. Standart mesh - size 6.5 mm; tolerance - 0.15 mm; draft quality mesh.

           7.2. Mesh control of the Rubber - size 3 mm; a/b - 1.5.

       

      I am attach picture of the coupling.