Wall-to-Bed Heat Transfer at Minimum Gas-Solid Fluidization
Table 2
Experimental results in the 21.6 cm I.D bed using a 1.0 cm O.D. heater.
Powder
(μm)
(kg/m3)
(cm/s)
(—)
(W/m2K)
(cm)
(W/mK)
Glass beads
55
2800
0.32
0.466
16.6
3.5
0.58
96
2800
0.95
0.457
18.6
2.9
0.54
173
2800
3.6
0.442
20.2
2.5
0.51
208
2800
3.8
0.440
22.8
2.4
0.55
407
2800
8.2
0.425
21.3
1.9
0.40
Angular sand
90
2540
1.23
0.590
18.3
3.3
0.60
106
2540
1.37
0.563
19.0
3.2
0.61
252
2540
5.3
0.498
32.1
2.6
0.83
470
2540
19.1
0.429
29.9
2.2
0.66
550
2540
29.5
0.414
34.0
2.1
0.71
778
2540
50.1
0.405
38.3
2.0
0.77
Rounded sand
152
2650
1.8
0.487
23.2
2.6
0.60
195
2650
3.2
0.432
23.8
2.4
0.57
197
2650
3.1
0.469
23.0
2.4
0.55
252
2650
4.9
0.453
25.9
2.2
0.57
435
2650
16.8
0.416
25.3
1.8
0.46
Diakon spheres
270
1180
3.3
0.426
23.3
2.2
0.51
Catalyst
38
1500
0.17
0.545
16.1
3.8
0.61
46
1500
0.23
0.543
12.5
3.7
0.46
58
1630
0.26
0.504
12.8
3.6
0.46
64
1630
0.28
0.502
14.5
3.6
0.52
Note: properties marked * were experimentally determined. Average particle sizes were measured by Malvern laser diffractometry. The absolute particle density was taken from suppliers’ data.
