Use case
It a Method of Turbulence Modeling where are all the Turbulent scales are resolved directly i.e, without averaging or using a turbulence model.
Requirements
- Mesh and Time resolution should be in the dissipative scale.
- Very High order schemes with super-low-dissipation
- Proper boundary conditions that supply instabilities.
- Large spatial and temporal domain that doesn’t constrain the development of Turbulence.
Effects of a Coarse mesh
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- The smaller eddies in the Dissipative scale are not simulated.
- This means that the Energy dissipation occurs at a smallest simulated scale (which given the mesh is bigger than the dissipative scale).
- Thus the bigger vortices rotate faster than normal to accommodate for this. This is non-physical and creates numerical instabilities.