Learning Forum

[wjdehgus902]

Hello,

I am trying to establish a multi-scale workflow in which profile outputs from a macro-scale simulation are used as input data for meso- and micro-scale analyses.

At this stage, I am not only looking for a simple data-transfer method, but also for guidance on how to define a consistent coupling procedure between scales.

In particular, I would like to understand the following:

1. How should I determine which macro-scale output variables are the most appropriate to pass down to the meso- and micro-scale models?
2. When transferring profile data across scales, is it better to use the raw profile directly, or to convert it into representative quantities/features first?
3. What is the recommended way to map macro-scale profile results to smaller-scale input conditions when the spatial/temporal resolution and meshes are different?
4. How should such transferred data be treated at the lower scale: as boundary conditions, initial conditions, or material/structural parameters?
5. Are there any common best practices for maintaining physical consistency during this scale-linking process?

I am especially interested in practical approaches within ANSYS Fluent or related workflows, but general guidance on multi-scale coupling would also be very helpful.

Thank you in advance.

[Rob]

For a "simple" one way link use profiles which would be set as a boundary condition in the smaller model. It is possible to use System Coupling to link two sessions but that would more usually be for separated flow domains (eg shell and tubeside in a heat exchanger). Profiles will interpolate from the table data to the nearest point in the new model, so make sure the surfaces are in the same location.