Theoretical and experimental study on hydrodynamic characteristics of fluidization in air–sand conical beds

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• 作者：Rachadaporn Kaewklum ; Vladimir I. Kuprianov
• 关键词：Particle size ; Static bed height ; Cone angle ; The ; none ; color ; black"" href=""/science?_ob=MathURL&_method=retrieve&_udi=B6TFK-4R8MDSW-1&_mathId=mml45&_user=10&_cdi=5229&_rdoc=8&_acct=C000050221&_version=1&_useri
• 刊名：Chemical Engineering Science
• 出版年：2008
• 出版时间：March 2008
• 年：2008
• 卷：63
• 期：6
• 页码：1471-1479
• 全文大小：271 K

文摘

This work was aimed at modeling hydrodynamic characteristics of fluidization in conical beds using quartz sand as the inert bed material and air as the fluidizing agent. The minimum fluidization velocity, u_mf, and the minimum velocity of full fluidization, u_mff, were determined by Peng and Fan's models modified for conical fluidized bed. Meanwhile, the pressure drop across a bed, Δp (including Δp_max and Δp_mff corresponding to u_mf and u_mff, respectively), was predicted by using modified Ergun's equations for variable superficial air velocity at an air distributor, u₀. The predicted results were validated by experimental data for some operating conditions. Effects of the sand particle size, cone angle and static bed height on the fluidization pattern and hydrodynamic characteristics are discussed. With the proposed models, the Δp–u₀ diagram were obtained with rather high accuracy for the conical air–sand beds of 30–45 cone angles and 20–30 cm static bed heights, when using 300– sand particles. For the predicted u_mf and u_mff, the relative computational errors were found to be within 20 % for wide ranges of operating variables, whereas Δp_max and Δp_mff could be predicted with lower (10–15 % ) relative errors. With higher cone angles and/or bed heights, the computational accuracy was found to deteriorate.