Studies on fluidization. II—heat transfer
Studies on fluidization. II—heat transfer
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流态化研究II——传热。
DOI：
10.1016/0009-2509(51)85001-2
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发表时间：
1951
影响因子：
4.7
通讯作者：
D. V. Krevelen
中科院分区：
文献类型：
--
作者：
C. V. Heerden;P. Nobel;D. V. Krevelen
在小规模装置中，在强烈变化的气体和固体条件下测量流化床（“密相”）的圆柱形壁的传热系数。使用的固体是紧密尺寸的样品以及不同尺寸的碳硅石、氧化铁（Fe 3 O 4）、焦炭、铅、Devarda合金和飞灰的混合物。使用的气体是空气、氮氢混合物、二氧化碳、氩气、城市煤气和甲烷。为了测量结果的相关性，使用了无量纲数系统，该系统可以被认为是所有可能影响传递系数值的变量的完整表示。气体速率的特征在于折合质量速度G/G 0，其中G 0是流化开始时的质量速度。当Re < 5时，此关联式是成功的，并可表示为：当2 <G/G 0 < 20时，当Re（G/G 0）= 0.028（G/G 0）= 0.45;更大的区域（1 <G/G_0 < 30）可以用本文第一部分中引入的广义形状因子B来覆盖，上述关系可以转换为限制在2 <G/G 0 < 20区域内的相关性。这可以写为其中对于Re < 5，x（B Re）= 0.58（B Re）0.45。
In a small scale apparatus the heat transfer coefficient to the cylindrical wall of a fluidizing bed (“dense phase”) was measured under strongly varying conditions of gas and solids. The solids used were closely sized samples as well as mixtures of different sizes of carborundum, ironoxide (Fe3O4), coke, lead, Devarda's alloy, and fly ash. The gases used were air, mixtures of nitrogen and hydrogen, carbon dioxide, argon, town's gas and methane.For a correlation of the measuring result use is made of a system of dimensionless numbers that may be considered as a complete representation of all variables which may be expected to influence the value of the transfer coefficient. The gas rate is characterized by the reduced mass velocityG/G0whereG0is the mass velocity at which fluidization starts. A correlation based on this variable proves to be successful forRe< 5 and can be written as: when ψ(G/G0) = 0,028(G/G0)0.45for 2 <G/G0< 20; a larger region (1 <G/G0< 30) can be covered byWith the aid of the generalized shape factorBintroduced in Part I of this study, the above mentioned relationship can be transformed into a correlation restricted to the region 2 <G/G0< 20. This can be written as where forRe< 5, χ (B Re) = 0,58 (B Re)0.45.