Calibration/Scale Up Hopper Design
Hello together
I'm currently trying to optimize the funnel design of an ash hopper for my master's project. I'm relatively new to DEM Simulations.
I've done the flow function measurements on the ash with the Schulze-RSX Shear tester and wanted to do the calibration with the given Calibration package. So far so good.
The problem is that with the student version I will not be able to simulate the 1mm sized ash particles and wanted to scale them up to 8mm to fit the geometry I have so far.
The given calibration kit cannot work reasonably with particles bigger than 4mm. Or i am just not doing it right. With bigger particles there just wont be a yield locus and the stresses show significant spikes in comparison to the given pre shearing normal stress for the shear cell.
Im using Hertz-Mindlin with the standard rolling friction so the scale up should not be the problem if the calibration is done right.
Is there any way to get the calibration running with lets say 2mm spheres and then scale down the existing geometry with factor 0,25. Would that add up to a scaling factor of 8 in total? Is there then a different scaling law for the geometry that i would need to adjust to...I'm a bit stumped on that.
Thank you very much in advance for helping me out.
Hi Kevin,
Replicating the geometry of the instrument is unnecessary. It is sufficient to impose the relevant stress state on a representative sample of material. This approach resolves the problem of accommodating large particle in the physical geometry. Please take a look at this article for further detail and an example:
Modelling a shear cell test in EDEM
Best regards,
Stefan