کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
237054 465692 2012 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A comparison of magnetic resonance imaging and electrical capacitance tomography: An air jet through a bed of particles
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
A comparison of magnetic resonance imaging and electrical capacitance tomography: An air jet through a bed of particles
چکیده انگلیسی

Magnetic resonance imaging (MRI) and electrical capacitance volume tomography (ECVT) have been compared for the visualisation of a jet of air issuing from a distributor provided with a single orifice and supporting a bed of poppy seeds contained in a vertical tube of 50 mm diameter. The mean diameter of the seeds was 1.2 mm: the orifice was 4 mm in diameter. MRI and ECVT images were acquired in three dimensions for flow rates of air such that, when divided by the cross-sectional area of the tube, they gave superficial velocities below that required for minimum fluidisation. The ECVT images were found to be of lower contrast (as well as resolution) than the MRI, owing to smoothing inherent to the ECVT reconstruction process. An adaptive threshold method is developed to recover the 3D structure of the jet from the ECVT results. This method describes the smoothing in the ECVT images by a point-spread function that can be objectively defined by comparison with the MRI results. Using the new adaptive threshold method, the maximum discrepancy in the measured jet length by ECVT was an overestimation by 7 mm in comparison with the MRI results. The discrepancies in the measured maximum jet widths appeared to be ca. 2 mm.

Images of the boundary of an air jet entering a bed of poppy seeds, through an orifice of diameter 4 mm. These images were determined from MRI (top row) and ECVT (bottom row) experiments for three different air flow rates.Figure optionsDownload as PowerPoint slideHighlights
► MRI and ECVT were compared for a single air jet through a bed of particles.
► A novel adaptive thresholding method for the ECVT images is presented.
► The image resolution of ECVT was estimated to be on the order of 10 mm.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Powder Technology - Volume 227, September 2012, Pages 86–95
نویسندگان
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