TY - JOUR
T1 - Structure-transport correlation for the diffusive tortuosity of bulk, monodisperse, random sphere packings
AU - Khirevich, Siarhei
AU - Höltzel, Alexandra
AU - Daneyko, Anton
AU - Seidel-Morgenstern, Andreas
AU - Tallarek, Ulrich
N1 - Funding Information:
This work was supported by the Deutsche Forschungsgemeinschaft DFG (Bonn, Germany) under grants TA 268/4-1 and TA 268/5-1 . Computational resources on IBM BlueGene ® /P platforms were provided by “Genius” at RZG (Rechenzentrum Garching, Germany) and “Jugene” at FZJ (Forschungszentrum Jülich, Germany). We thank the DEISA Consortium ( http://www.deisa.eu/ ), co-funded through the EU FP6 project RI-031513 and the FP7 project RI-222919, for support within the DEISA Extreme Computing Initiative. We are also grateful to the Jülich Supercomputing Centre (JSC) for allocation of a special CPU-time grant (project HMR10).
PY - 2011/9/16
Y1 - 2011/9/16
N2 - The mass transport properties of bulk random sphere packings depend primarily on the bed (external) porosity e{open}, but also on the packing microstructure. We investigate the influence of the packing microstructure on the diffusive tortuosity τ=Dm/Deff, which relates the bulk diffusion coefficient (Dm) to the effective (asymptotic) diffusion coefficient in a porous medium (Deff), by numerical simulations of diffusion in a set of computer-generated, monodisperse, hard-sphere packings. Variation of packing generation algorithm and protocol yielded four Jodrey-Tory and two Monte Carlo packing types with systematically varied degrees of microstructural heterogeneity in the range between the random-close and the random-loose packing limit (e{open}=0.366-0.46). The distinctive tortuosity-porosity scaling of the packing types is influenced by the extent to which the structural environment of individual pores varies in a packing, and to quantify this influence we propose a measure based on Delaunay tessellation. We demonstrate that the ratio of the minimum to the maximum void face area of a Delaunay tetrahedron around a pore between four adjacent spheres, (Amin/Amax)D, is a measure for the structural heterogeneity in the direct environment of this pore, and that the standard deviation σ of the (Amin/Amax)D-distribution considering all pores in a packing mimics the tortuosity-porosity scaling of the generated packing types. Thus, σ(Amin/Amax)D provides a structure-transport correlation for diffusion in bulk, monodisperse, random sphere packings.
AB - The mass transport properties of bulk random sphere packings depend primarily on the bed (external) porosity e{open}, but also on the packing microstructure. We investigate the influence of the packing microstructure on the diffusive tortuosity τ=Dm/Deff, which relates the bulk diffusion coefficient (Dm) to the effective (asymptotic) diffusion coefficient in a porous medium (Deff), by numerical simulations of diffusion in a set of computer-generated, monodisperse, hard-sphere packings. Variation of packing generation algorithm and protocol yielded four Jodrey-Tory and two Monte Carlo packing types with systematically varied degrees of microstructural heterogeneity in the range between the random-close and the random-loose packing limit (e{open}=0.366-0.46). The distinctive tortuosity-porosity scaling of the packing types is influenced by the extent to which the structural environment of individual pores varies in a packing, and to quantify this influence we propose a measure based on Delaunay tessellation. We demonstrate that the ratio of the minimum to the maximum void face area of a Delaunay tetrahedron around a pore between four adjacent spheres, (Amin/Amax)D, is a measure for the structural heterogeneity in the direct environment of this pore, and that the standard deviation σ of the (Amin/Amax)D-distribution considering all pores in a packing mimics the tortuosity-porosity scaling of the generated packing types. Thus, σ(Amin/Amax)D provides a structure-transport correlation for diffusion in bulk, monodisperse, random sphere packings.
KW - Degree of heterogeneity
KW - Delaunay tessellation
KW - Effective diffusion and tortuosity
KW - Packing method and disorder
KW - Porosity scaling
KW - Voronoi volume distribution
UR - http://www.scopus.com/inward/record.url?scp=80051864716&partnerID=8YFLogxK
U2 - 10.1016/j.chroma.2011.07.066
DO - 10.1016/j.chroma.2011.07.066
M3 - Article
C2 - 21831382
AN - SCOPUS:80051864716
SN - 0021-9673
VL - 1218
SP - 6489
EP - 6497
JO - Journal of Chromatography A
JF - Journal of Chromatography A
IS - 37
ER -