[Guanzhu]

In foam extend, IBM is used to do an example to simulate the turbulence characteristics of a grid in a rectangular channel. I import the STL file of the grid into trisurfac to run the example. After I run the example, I find that only four corners of the imported grid work. What's the reason for this?
The channel size is 4 × 0.25 × 0.25m. The grid is conventional grid, the width of grid bar is 10 mm, the size of each small grid is 50 × 50 mm, and the total size of grid is 250 × 250 mm.
Now only four corner holes can be identified, but other holes have no effect, or can be identified. Then someone told me that it was the problem of grid density, so I made local encryption in the area near the grid: a 100W grid was built in the area of 0.25m × 0.25m × 0.25m. The total background grid is 400W, but other holes are still unrecognized.
Is my grid setting still not dense enough, or is it caused by other reasons?
Sorry, I don’t know why I can’t upload pictures or attachments. I can only describe the grid I use as much as possible.