title: The 3D pore structure and fluid dynamics simulation of macroporous monoliths: High permeability due to alternating channel width.
abstract: Polymethacrylate-based monoliths have excellent flow properties. Flow in the wide channel interconnected with narrow channels is theoretically assumed to account for favorable permeability. Monoliths were cut into 898 slices in 50nm distances and visualized by serial block face scanning electron microscopy (SBEM). A 3D structure was reconstructed and used for the calculation of flow profiles within the monolith and for calculation of pressure drop and permeability by computational fluid dynamics (CFD). The calculated and measured permeabilities showed good agreement. Small channels clearly flowed into wide and wide into small channels in a repetitive manner which supported the hypothesis describing the favorable flow properties of these materials. This alternating property is also reflected in the streamline velocity which fluctuated. These findings were corroborated by artificial monoliths which were composed of regular (interconnected) cells where narrow cells followed wide cells. In the real monolith and the artificial monoliths with interconnected flow channels similar velocity fluctuations could be observed. A two phase flow simulation showed a lateral velocity component, which may contribute to the transport of molecules to the monolith wall. Our study showed that the interconnection of small and wide pores is responsible for the excellent pressure flow properties. This study is also a guide for further design of continuous porous materials to achieve good flow properties.
authors.affiliation: Austrian Centre of Industrial Biotechnology, Muthgasse 11, 1190 Vienna, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Jungreuthmayer
authors.affiliation: Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria.
authors.forename: Petra
authors.initials: P
authors.lastname: Steppert
authors.affiliation: Austrian Centre of Industrial Biotechnology, Muthgasse 11, 1190 Vienna, Austria.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Sekot
authors.affiliation: Institute for Electron Microscopy and Nanoanalysis, Graz University of Technology, NAWI Graz, and Graz Centre for Electron Microscopy, Steyrergasse 17, 8010 Graz, Austria.
authors.forename: Armin
authors.initials: A
authors.lastname: Zankel
authors.affiliation: Institute for Electron Microscopy and Nanoanalysis, Graz University of Technology, NAWI Graz, and Graz Centre for Electron Microscopy, Steyrergasse 17, 8010 Graz, Austria.
authors.forename: Herbert
authors.initials: H
authors.lastname: Reingruber
authors.affiliation: Austrian Centre of Industrial Biotechnology, Muthgasse 11, 1190 Vienna, Austria.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Zanghellini
authors.affiliation: Austrian Centre of Industrial Biotechnology, Muthgasse 11, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria. Electronic address: alois.jungbauer@boku.ac.at.
authors.forename: Alois
authors.initials: A
authors.lastname: Jungbauer
mesh_terms: D057446:Hydrodynamics; D008855:Microscopy, Electron, Scanning; D008968:Molecular Conformation; D010539:Permeability; D011109:Polymethacrylic Acids / Q000737:chemistry*; D016062:Porosity; D011312:Pressure
chemical_list: D011109:Polymethacrylic Acids; C030613:polymethacrylic acid
keywords: CFD; Flow; Monoliths; Permeability; Polymethacrylate; Pressure drop