[keepfit]

Hi Foamers,

suppose there is a moving object in fluid. I want to know all cells (IDs) that intersects the object at EVERY timestep. Is there any way to avoid loop all cells in the fluid domain?

My idea is: first find the cell near the center of the object, then loop over the neighboring cells of the first cell. We repeat this process on preciously found cells until new cells are all outside the object. This way we don't need to loop over cells that are far away from the object.

Nevertheless, I am not familiar with existing OpenFOAM algorithms to do this job more efficiently. Any wonderful advice will be highly appreciated.