Sims of rathole in coal bin

Hi Michael,

Yes, the ratholing phenomenon has been modelled successfully in the past using DEM in general and EDEM in particular. You'll need to calibrate your material model using a flow function from a shear cell or a uniaxial unconfined compresison test as a benchmark.

You may find the below literature useful:

https://www.bulkhandlingreview.com.au/analysis-of-silo-asymmetry-normal-pressures-due-to-eccentric-discharge-using-dem-simulation/

https://www.sciencedirect.com/science/article/pii/S0263224119303872

https://www.sciencedirect.com/science/article/pii/S0032591009003088

Schwedes, J. (2003) ‘Review on testers for measuring flow properties of bulk solids’, Granular Matter, 5(1), pp. 1–43. doi: 10.1007/s10035-002-0124-4.

ASTM D6773-16 ‘Standard shear test method for bulk solids using the Schulze ring shear tester’, ASTM International, www.​ astm.​ org, i, pp. 1–27. doi: 10.1520/D6773-16.2.

Best regards,

Stefan

Many thanks Stefan. We had the test results and I read through the literatures as suggested, while still cannot achieve the rat holing. It will be great if you can suggest specific successful example. Appreciate.  

Many thanks Stefan. We had the test results and I read through the literatures as suggested, while still cannot achieve the rat holing. It will be great if you can suggest specific successful example. Appreciate.  

Hi Michael,

Unfortunately I'm not able to directly give you values for your coal model. You'll have to calibrate your model parameters using the above measurements as bechmarks so the first step would be to perform those measurements on your coal fines or identify values from literature (your national silo design codes should have generic data for coal fines). Then you can use the data to calibrate your model. Leveraging tools such as Altair HyperStudy may help with the calibration and we do offer calibraiton training:

HyperStudy-EDEM connector

EDEM Calibration training

Best regards,

Stefan