# Calibrating Syamlal-O'brien Drag Correlation

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 December 23, 2007, 14:13 Calibrating Syamlal-O'brien Drag Correlation #1 mrt Guest   Posts: n/a Dear All, My questions are about calibrating Syamlal-O'Brien drag correlation. (After I find parameters (c and d), I will write UDF for my particles but unfortunately I couldn't find the literature values for starters.) My questions: 1) In the article (Fluid dynamic simulation of O3 decomposition in a bubbling fluidized bed, AIChE Journal, 2003, Volume 49, No. 11, Pages: 2793-..,by Syamlal, M. and T.J. O'Brien) , for sand particles Particle diameter = 117 micrometer Particle density = 2650 kg/m3 Minimum fluidization velocity = 1.70 cm/s Void fraction at minimum fluidization = 0.48 And with assumptions: Air density = 1.205 kg/m3 Air dynamic viscosity = 1.82*10^(-5) kg/(m.s) After I solve myself, I find different c&d (than the real solution: C = 0.765 and D = 2.93) and then try other way around. With c and d I calculate minimum fluidization velocity as = 0.03460 m/s (which is double of actual value). I am confused a bit.Can anyone help me on this? 2) I was wondering if you know how I can get this spreadsheet: "Syamlal, M., Fluent Inc. Personal communication, spread sheet sent directly to first author for drag correlations (1999)". It is about an iterative procedure that helps to find the c&d values (of syamlal-obrien drag correlation) for specific particles. It is cited as reference in the article "CFD simulations of bubbling/collapsing fluidized beds for three geldart groups, AIChE Journal, 2003, April, Volume 49, No. 4, Pages: 844-858, Gelderbloom, Susan J.; Dimitri Gidaspow and Robert W. Lyczkowski" regards,

 December 30, 2007, 18:15 Re: Calibrating Syamlal-O'brien Drag Correlation #2 shehab abdelrahman Guest   Posts: n/a hi there: i'm working in the same area and possibly we can benefit from our experience together. I can help you finding this paper but first can you give me the specific information about the paper you want...next, please, can you tell me about what your field of research in details..because i have something good for you... shehab

 July 12, 2013, 04:22 #3 New Member   massoud Join Date: Nov 2011 Posts: 20 Rep Power: 14 Dear Mrt hi, I want to find the value of C and D too. could you finally find out what was the problem in your calculation? if yes could you please tell me how I should modify syamlal-Obrien drag force based on minimum fluidization velocity? thank you in advance,