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DOE OSTI · 1869680

Machine learning accelerated discrete element modeling of granular flows

Lu, Liqiang·Gao, Xi·Dietiker, Jean-François·Shahnam, Mehrdad·Rogers, William A.
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Abstract

Granular flows are widely encountered in many industrial processes and natural phenomena. Discrete Element Modeling (DEM) is a useful tool for understanding and troubleshooting devices, which handle granular materials. However, its applicability is significantly limited by the huge computational cost associated with detecting and computing collisions. In this research, the computation speed of DEM was accelerated by orders of magnitude using a convolutional neural network to replace the direct calculation of particle-particle and particle-boundary collisions. The MFiX software was used to generate the training and testing dataset. Additionally, a GPU accelerated TensorFlow model was used to train the neural network and test the results. The model fluctuations caused by different training steps were reduced with a multi-scale loss function. The accuracy was improved with more frames within one training step. The modeling of a rotating drum and a hopper demonstrated the accuracy and efficiency of this machine learning accelerated DEM in the simulation of granular flows.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYTensorFlowconvolutional neural networkdiscrete element modelinggranular flowmachine learning

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Lu, Liqiang, Gao, Xi, Dietiker, Jean-François, Shahnam, Mehrdad, Rogers, William A.. 2021-06-02. Machine learning accelerated discrete element modeling of granular flows. https://doi.org/10.1016/j.ces.2021.116832

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