Greetings all,
In one of my simulations where the base size is 0.5 m, as the DFBI releases there is a hike in drag and residuals (up to 100) in certain intervals with some reversed flow. When I change my base size into 5m, the reflection and the sudden hike in the residuals (all less than one) and drag vanishes.
The question is how these hike vanishes and the residuals become less than one as I coarsen the mesh? ? All my mesh quality checks are in the range for both the conditions.
Howdy Anagha R H ,
You need a response from someone doing programming in this millennium, but I can offer a general answer.
The details are lost to smoothing or just being missed by the calculations on the coarse grid. This is a condition of digitizing anything. Your photo with 16 pixels probably does not show you have eyebrows, but with 16 megapixels your features become quite clear. If you could afford the cost of using a 0.05 m base size further details would appear, but you would still have the task of separating computational side-effects from the true fluid dynamics of your simulations.
Happy Trails,
Len
Hi Leonard Hall , I hope you are doing well.
Thank you for the insight.
As you said , coarse meh can affect the numerical stability and and resolution of flow especially as the DFBI is involved. I was a bit surprised by the drop in residuals cause I expected them to be higher as I coarsen the mesh.
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