My Fatigue code for FEMAP & NX NASTRAN is winLIFE based in Germany (http://www.stz-verkehr.de/e_winlife.php): not only the software is great, really powerfull, very good integrated with FEMAP (bidirectional input/output) but also the development team of winLIFE is excepcionaly professional, the best!.Totally recomended, you will be impressed of the knowledge of Prof. Dr. Günter Willmerding, very helpful!!.
No, winLIFE QUICK-CHECK module do not perform strain-life Fatigue analysis, QUICK-CHECK is for those FEM/FEA users that wish to make fatigue life predictions easily, but not any information on the load spectrum, the S-N curves, surface, isotropy etc. is available. Despite this, they still wish to make at least a rough estimate on whether any fatigue strength problems are to be expected. The Endurance Limit Certification performed by winLIFE QUICK CHECK module can help to answer such questions. If it is possible to safely show that in a worst-case-scenario the stress is below the endurance limit, then this result is often sufficient and more extensive fatigue strength tests are not necessary.
The Endurance Limit Certification performed by QUICK-CHECK cannot give you the fatigue life, but a prediction as to whether the worst-case-scenario is below the endurance limit and if so, by how much. If the endurance limit certification is not fulfilled, then it will be necessary to carry out much more detailed fatigue life tests using winLIFE professional modules. For these, you will need, in particular, the loads and their time relation.
The main target is to achieve fatigue results with very little action by the user. The proof is based on FEM calculations and for every load Fi (force, torque, temperature), which has an effect on the component you must have a static FEA Stress results for the maximum value. For each load case having an effect on the component, only
is taken into account. The number of load cycles is not considered in the calculation. The stress tensors on all nodes are used for the analysis. To describe the material you only need the endurance limit and its dependence on the mean stress.
To calculate the safety against the endurance limit, a calculation of all possible combinations of the stress tensors for all load cases is carried out and superimposed. The process is shown in the following picture:
The following picture shows back in FEMAP the Fatigue results computed by QUICK CHECK for a problem with three load cases. The interaction of the three loadcases is designated by the resulting degree of utilization. A value of 1.0 signifies the endurance limit is reached. The here reached value is of 0.233 means that the endurance limit is used to 23,3 %. The safety to endurance limit corresponds to the inverse of the degree of utilization and is 4,275.