Bin Zhang^1,2, Yiming Huang^3,4, Tingting Zhao^5,*

CMES-Computer Modeling in Engineering & Sciences, Vol.127, No.3, pp. 1133-1150, 2021, DOI:10.32604/cmes.2021.016018

Abstract The simulation of a large number of particles requires unacceptable computational time that is the most critical problem existing in the industrial application of the DEM. Coarse graining is a promising approach to facilitate the application of DEM to industrial problems. While the current coarse graining framework is often developed in an ad-hoc manner, leading to different formulations and different solution accuracy and efficiency. Therefore, in this paper, existing coarse graining techniques have been carefully analysed by the exact scaling law which can provide the theory basis for the upscaling method. A proper scaling rule for the size of particles… More >

Yohei Inoue, Taishi Nakamura, Shuji Ogata, Ryo Kobayashi, Toshiyuki Gotoh

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 49-50, 2011, DOI:10.3970/icces.2011.020.049

Abstract No proper simulation method exists in between the molecular simulation method at nanometer scale using the first principles or empirical inter-molecular interaction and the continuum simulation method at micrometer-plus scale. The nanotechnology deals principally with those systems whose characteristic scales reside in such a scale-gap. Considering this, we develop a sequential scale-up scheme starting from the atomistic up to micrometer-plus scales. In the present paper we take, as an example, the system of graphenes that may or may not be fluttering in airflow, and apply to it our sequential scale-up scheme to see its capability.

The graphene is unique… More >

Y. Inoue¹, R. Kobayashi¹, S. Ogata¹, T. Gotoh¹

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.2, pp. 137-162, 2010, DOI:10.3970/cmes.2010.063.137

Abstract Vibration of a single graphene and a pair of graphenes at micro meter scale induced by air flow is numerically simulated and examined by using a hybrid computational method starting from a microscopic level of description for the graphene. In order to bridge a huge gap in spatial and time scales in their motions, the carbon atoms of the graphene are represented by a small number of coarse grained particles, the fluid motion is described by the lattice Boltzmann equation and the momentum exchange at the boundary is treated by the time averaged immersed boundary method. It is found that… More >