NASA LogoNTRSNTRS - NASA Technical Reports ServerSearchmore_vertCollectionsAboutNewsHelpLogin Back to ResultsVirtual and Experimental Visualization of Flows in Packed Beds of Spheres Simulating Porous Media FlowsA videotape presentation of flow in a packed bed of spheres is provided. The flow experiment consisted of three principal elements: (1) an oil tunnel 76.2 mm by 76.2 mm in cross section, (2) a packed bed of spheres in regular and irregular arrays, and (3) a flow characterization methodology, either (a) full flow field tracking (FFFT) or (b) computational fluid dynamic (CFD) simulation. The refraction indices of the oil and the test array of spheres were closely matched, and the flow was seeded with aluminum oxide particles. Planar laser light provided a two-dimensional projection of the flow field, and a traverse simulated a three-dimensional image of the entire flow field. Light focusing and reflection rendered the spheres black, permitting visualization of the planar circular interfaces in both the axial and transverse directions. Flows were observed near the wall-sphere interface and within the set of spheres. The CFD model required that a representative section of a packed bed be formed and gridded, enclosing and cutting six spheres so that symmetry conditions could be imposed at all cross-boundaries. Simulations had to be made with the flow direction at right angles to that used in the experiments, however, to take advantage of flow symmetry. Careful attention to detail was required for proper gridding. The flow field was three-dimensional and complex to describe, yet the most prominent finding was flow threads, as computed in the representative 'cube' of spheres with face symmetry and conclusively demonstrated experimentally herein. Random packing and bed voids tended to disrupt the laminar flow, creating vortices.Document ID19980231080Acquisition SourceLegacy CDMSDocument TypeReprint (Version printed in journal)AuthorsHendricks, R. C.*(NASA Lewis Research Center Cleveland, OH United States)*Athavale, M. M.*(CFD Research Corp. Huntsville, AL United States)*Lattime, S. B.*(B and C Engineering Associates, Inc. Akron, OH United States)*Braun, M. J.*(Akron Univ. Akron, OH United States)*Date AcquiredSeptember 6, 2013Publication DateAugust 1, 1998Subject CategoryFluid Mechanics And Heat TransferReport/Patent NumberE-11214NAS 1.15:207926NASA/TM-1998-207926Meeting InformationMeeting: Flow VisualizationLocation: SorrentoCountry: ItalyStart Date: September 1, 1998End Date: September 4, 1998Sponsors:Naples Univ.,Heriot-Watt Univ.Funding Number(s)PROJECT: RTOP 910-30-11Distribution LimitsPublicCopyrightWork of the US Gov. Public Use Permitted.Available DownloadsNameType19980231080.pdfSTIcloud_downloadcontent_copyvisibilityRelated RecordsThere are no records associated with this record.visibility_offNo Preview Available
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