ProductsAbaqus/StandardAbaqus/Explicit Mullins effect in elastomersElements testedSAX1 CPS4R CPE4R CPE4RH C3D8R C3D8RH T2D2 Problem descriptionThe problems in this set can be broadly classified under three categories. The first category of problems consists of simple displacement- or load-controlled cyclic tests to verify the Mullins effect, with the primary response defined by different strain energy potential functions. The tests consist of a single element that is cyclically loaded to a maximum strain (stress) level, then unloaded to zero strain (stress). This is followed by further reloading to levels of strain (stress) that are higher than those reached during the loading segment of the first cycle, followed again by unloading to zero strain (stress). The tests in this section use parts and assemblies. The second category of problems is intended for testing the calibration capabilities for determining the Mullins effect coefficients. The problems use unloading test data that were generated by running a model with specified values of the Mullins effect coefficients. The calibration capability is meant to recover the specified values of the Mullins effect coefficients. These tests use different loading states, such as uniaxial tension, biaxial tension, and planar tension. The third category of problems tests the import capability with the Mullins effect. All tests in this section are set up with a uniaxial stress state. The tests consist of first loading a single element in Abaqus/Standard and unloading it. The results are then imported into Abaqus/Explicit, where the element is loaded to deformation levels higher than the original loading and then unloaded. These results are again imported back into Abaqus/Standard, where the element is loaded to deformation levels higher than the prior loading and then unloaded. Finally, the last set of results are imported from Abaqus/Standard to Abaqus/Standard, and the element is further deformed and unloaded. The above series of tests includes problems that import both the state and the reference configuration, problems that import only the state, and problems that import neither the state nor the reference configuration. Material:The following material data are used for the first category of tests:
For the second and third category of tests the primary material response is defined using the incompressible Yeoh potential with the deviatoric coefficients as given above. For the second category of tests the unloading test data are generated for uniaxial, biaxial, and planar stress states using the following values for the Mullins effect parameters: r = 1.25, m = 0.01, and = 0.9. These parameters are also used to define the Mullins effect in the third category of tests. Loading:The first category of problems includes both displacement- and force-controlled loading. The second and third categories of problems are carried out under only displacement-controlled loading. Results and discussionFor the first category of problems the results of the Abaqus/Standard and Abaqus/Explicit numerical simulations are in good agreement with the analytical results. For the second category of problems, which tests the calibration of the Mullins effect parameters, it is observed that the parameters r and are always captured accurately. A good fit for m is obtained in situations where the deformation level leads to a relatively large value of maximum deviatoric strain energy density, , such that the value of dominates over the value of m. For the final category of problems, which tests the import capability, the response after each import of results is as expected. When the state is imported, further deformation upon import shows the appropriate level of stress softening. On the other hand, when the state is not imported, no stress softening is observed. Input files
Permanent set in elastomersElements testedC3D8 C3D8H C3D8R C3D8RH CAX4R CGAX4RH CPS3 CPS4R CPS6M CPS8 S3R S4R SC8R M3D4R Problem descriptionAll problems in this section verify hyperelastic behavior with Mullins effect and plasticity. Comparison of finite element results can be made against the original test data (stress versus total strain) supplied with the input files. Most problems use test data as input for hyperelastic behavior and Mullins effect in a stress-free configuration. Similarly, plasticity is defined using a suitable hardening function. The problems in this set can be broadly classified under two categories. The first category of problems consists of displacement- or load-controlled cyclic tests in modes such as uniaxial tension, biaxial tension, and simple shear with or without orientation. These problems verify simulation of permanent set with Mullins effect for various hyperelastic models. The second category of problems is intended for testing the import capability with permanent set. Various combinations of elements and modes of deformation are verified for import from Abaqus/Standard to Abaqus/Explicit, from Abaqus/Standard to Abaqus/Standard, and from Abaqus/Explicit to Abaqus/Standard. Material:Refer to the input files for test data and material properties used. Loading:Both displacement- and load-controlled loading are used to verify uniaxial and biaxial tension. Only displacement-controlled loading is used to verify simple shear mode. Results and discussionThe results of the finite element simulation can be compared with the original test data input provided in separate files, and the agreement is very good. Input files
Energy dissipation in elastomeric foamsElements testedCPS4R C3D8R T3D2 Problem descriptionThe problems in this set can be broadly classified under three categories. The first category of problems consists of simple displacement- or load-controlled cyclic tests to verify the effect of energy dissipation in elastomeric foams. The tests consist of a single element that is cyclically loaded to a maximum strain (stress) level, then unloaded to zero strain (stress). This is followed by further reloading to levels of strain (stress) that are higher than those reached during the loading segment of the first cycle, followed again by unloading to zero strain (stress). The tests in this section use parts and assemblies. The second category of problems is intended for testing the calibration capabilities for determining the Mullins effect coefficients. The problems use unloading test data that were generated by running a model with specified values of the Mullins effect coefficients. The calibration capability is meant to recover the specified values of the Mullins effect coefficients. These tests use different loading states, such as uniaxial tension, biaxial tension, and planar tension. The third category of problems tests the import capability. All tests in this section are set up with a uniaxial stress state. The tests consist of first loading a single element in Abaqus/Standard. The results are then imported to Abaqus/Explicit, where the element is unloaded. These results are again imported back into Abaqus/Standard, where the element is loaded to deformation levels higher than the prior loading. Finally, the last set of results are imported from Abaqus/Standard to Abaqus/Standard, and then the element is unloaded. The above series of tests includes problems that import both the state and the reference configuration, problems that import only the state, and problems that import neither the state nor the reference configuration. Material:The following material data are used for the first category of tests:
Loading:The first category of problems includes both displacement- and force-controlled loading. The second and third categories of problems are carried out under only displacement-controlled loading. Results and discussionFor the first category of problems the results of the Abaqus/Standard and Abaqus/Explicit numerical simulations are in good agreement with the analytical results. For the second category of problems, which tests the calibration of the Mullins effect parameters, it is observed that the parameters r and are always captured accurately. A good fit for m is obtained in situations where the deformation level leads to a relatively large value of maximum deviatoric strain energy density, , such that the value of dominates over the value of m. For the final category of problems, which tests the import capability, the response after each import of results is as expected. When the state is imported, further deformation upon import shows the appropriate level of stress softening. On the other hand, when the state is not imported, no stress softening is observed. Input files
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