The turbulence model is a mathematical model one which resembles the physical model of the problem. How I can identify that this particular turbulence model is suitable for that physical model.
I think that, depending on the flow problem, you have to ask what "right" formulation you should use. A physical problem could be simulated using several formulations (RAN/URANS/DES/LES) each one having several turbulence models.
Thus, you should provide the full details of your problem.
You should try different turbulence model for your case and analyze their results using statistical parameter! or you can find similar case in previous studies
I think it depend on your physical problem (geometry structure) and flow range as Mr. Denaro mentioned above, for instance, with high turbulent flows Re grater than 5000 for internal flow without of expected regions of separation it high recommended to use K-epsilon standard model and with expected of flow separation K-epsilon RNG or Realizable models recommended. you can look at fluent theory guide for turbulence modeling for more informations. regards
Turbulence models differ in how they model the flow close to walls (wall function approximation near the walls or solving the hydrodynamic problem everywhere), the number of additional variables solved for, and what these variables represent. All of that results in different accuracy of solution. k-e model is a good choise to begin. But more accurate results can be obrained using SST model.
For deeper understanding you can read this article: https://www.comsol.com/blogs/which-turbulence-model-should-choose-cfd-application/.
We cannot generalise that a particular turbulence modelling is suitable for a particular problem. Be careful in meshing when different types are used. y + values near wall is different for different models. If accuracy is not an issue , k-e model is okey. For design optimisation u can use similar models for all geometries. It is better to see the guide lines in FLUENT tutorials and manuals before applying any model. They have done many different types of problems in tutorials. Pls refer FLUENT Tutorials for better guidance based on the type of problem u r solving. They have used different turbulence models for different type of problems based on experimentation validation. So we can try those and check the accuracy by validation.
I think it depend on nature of turbulence : free turbulence (like jet or wake) or wall turbulence.You can see the help in fluent
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