A numerical study of the effects of the shape of an enclosed screw conveyor on the mixing and heat transfer in a horizontal gas–solid fluidized bed was conducted using computational fluid dynamics (CFD). A two-fluid model (TFM) was employed to model the gas and solid phases as continua through mass, momentum, and energy conservations. The motion of the screw conveyor was simulated by using a rotating reference frame (RRF) such that the computational mesh was free from dynamic reconstruction. The diameters of the screw flight and shaft, the pitch, and the blade thickness were varied in the parametric study. Under the operating conditions studied, it was found that the increase in the diameter of the screw flight results in the enhancement of the solid mixing and conveyance. The increase in the diameters of the screw shaft and the screw blade thickness lead to the enhanced solid mixing but reduced conveyance. The variation in the screw pitch gives rise to rather complex behaviors in the solid mixing and conveyance. As the screw pitch is decreased, the solid mixing increases initially but then decreases before it increases eventually. The solid conveyance capability was found to first increase and then decrease. Explanations to the effects of the shape of the screw conveyor were discussed in this work.

References

1.
Buick
,
J.
,
2009
, “
Lattice Boltzmann Simulation of Power-Law Fluid Flow in the Mixing Section of a Single-Screw Extruder
,”
Chem. Eng. Sci.
,
64
(
1
), pp.
52
58
.10.1016/j.ces.2008.09.016
2.
Soavi
,
F.
,
Zurla
,
O.
, and
Levi
,
R.
,
1990
, “
A New Type of Screw Conveyor for Metallic Chips
,”
CIRP Ann. Manuf. Technol.
,
39
(
1
), pp.
399
404
.10.1016/S0007-8506(07)61082-8
3.
Moysey
,
P.
, and
Thompson
,
M.
,
2004
, “
Investigation of Solids Transport in a Single-Screw Extruder Using a 3-D Discrete Particle Simulation
,”
Polym. Eng. Sci.
,
44
(
12
), pp.
2203
2215
.10.1002/pen.20248
4.
Yu
,
Y.
, and
Arnold
,
P.
,
1996
, “
The Influence of Screw Feeders on Bin Flow Patterns
,”
Powder Technol.
,
88
(
1
), pp.
81
87
.10.1016/0032-5910(96)03107-5
5.
Zhong
,
Z.
, and
O'Callaghan
,
J.
,
1990
, “
The Effect of the Shape of the Feed Opening on the Performance of a Horizontal Screw Conveyor
,”
J. Agric. Eng. Res.
,
46
, pp.
125
128
.10.1016/S0021-8634(05)80120-9
6.
Soavi
,
F.
, and
Zurla
,
O.
,
1997
, “
Performance Evaluation of a New Screw Conveyor for Metal Swarf
,”
Int. J. Mach. Tools Manuf.
,
37
(
7
), pp.
981
996
.10.1016/S0890-6955(96)00062-4
7.
Roberts
,
A.
,
1999
, “
The Influence of Granular Vortex Motion on the Volumetric Performance of Enclosed Screw Conveyors
,”
Powder Technol.
,
104
(
1
), pp.
56
67
.10.1016/S0032-5910(99)00039-X
8.
Yu
,
Y.
, and
Arnold
,
P.
,
1997
, “
Theoretical Modelling of Torque Requirements for Single Screw Feeders
,”
Powder Technol.
,
93
(
2
), pp.
151
162
.10.1016/S0032-5910(97)03265-8
9.
Dai
,
J.
, and
Grace
,
J. R.
,
2008
, “
A Model for Biomass Screw Feeding
,”
Powder Technol.
,
186
(
1
), pp.
40
55
.10.1016/j.powtec.2007.10.032
10.
Waje
,
S.
,
Thorat
,
B.
, and
Mujumdar
,
A.
,
2006
, “
An Experimental Study of the Thermal Performance of a Screw Conveyor Dryer
,”
Drying Technol.
,
24
(
3
), pp.
293
301
.10.1080/07373930600564506
11.
Sabarez
,
H. T.
, and
Noomhorm
,
A.
,
1993
, “
Performance Testing of an Experimental Screw Conveyor Dryer for Roasting Cashew Nuts
,”
Postharvest Biol. Technol.
,
2
(
3
), pp.
171
178
.10.1016/0925-5214(93)90045-5
12.
Waje
,
S.
,
Patel
,
A.
,
Thorat
,
B.
, and
Mujumdar
,
A.
,
2007
, “
Study of Residence Time Distribution in a Pilot-Scale Screw Conveyor Dryer
,”
Drying Technol.
,
25
(
1
), pp.
249
259
.10.1080/07373930601161120
13.
Owen
,
P.
, and
Cleary
,
P.
,
2009
, “
Prediction of Screw Conveyor Performance Using the Discrete Element Method (DEM)
,”
Powder Technol.
,
193
(
3
), pp.
274
288
.10.1016/j.powtec.2009.03.012
14.
Hou
,
Q.
,
Dong
,
K.
, and
Yu
,
A.
,
2014
, “
DEM Study of the Flow of Cohesive Particles in a Screw Feeder
,”
Powder Technol.
,
256
, pp.
529
539
.10.1016/j.powtec.2014.01.062
15.
Fernandez
,
J. W.
,
Cleary
,
P. W.
, and
McBride
,
W.
,
2011
, “
Effect of Screw Design on Hopper Drawdown of Spherical Particles in a Horizontal Screw Feeder
,”
Chemi. Eng. Sci.
,
66
(
22
), pp.
5585
5601
.10.1016/j.ces.2011.07.043
16.
Dai
,
J.
, and
Grace
,
J. R.
,
2008
, “
Biomass Screw Feeding With Tapered and Extended Sections
,”
Powder Technol.
,
186
(
1
), pp.
56
64
.10.1016/j.powtec.2007.10.033
17.
Agirre
,
I.
,
Griessacher
,
T.
,
Rösler
,
G.
, and
Antrekowitsch
,
J.
,
2013
, “
Production of Charcoal as an Alternative Reducing Agent From Agricultural Residues Using a Semi-Continuous Semi-Pilot Scale Pyrolysis Screw Reactor
,”
Fuel Process. Technol.
,
106
, pp.
114
121
.10.1016/j.fuproc.2012.07.010
18.
Brown
,
J.
, and
Brown
,
R.
,
2012
, “
Process Optimization of an Auger Pyrolyzer With Heat Carrier Using Response Surface Methodology
,”
Bioresour. Technol.
,
103
(
1
), pp.
405
414
.10.1016/j.biortech.2011.09.117
19.
Wan
,
Y.
, and
Hanley
,
T. R.
,
2004
, “
Computational Fluid Dynamics Simulation and Redesign of a Screw Conveyor Reactor
,”
Appl. Biochem. Biotechnol.
,
114
(
1–3
), pp.
733
745
.10.1385/ABAB:114:1-3:733
20.
Berson
,
R. E.
, and
Hanley
,
T. R.
,
2005
, “
Use of Computational Fluid Dynamics Simulations for Design of a Pretreatment Screw Conveyor Reactor
,”
Appl. Biochem. Biotechnol.
,
124
(
1–3
), pp.
935
945
.10.1385/ABAB:124:1-3:0935
21.
Berson
,
R. E.
,
Dasari
,
R. K.
, and
Hanley
,
T. R.
,
2006
, “
Modeling of a Continuous Pretreatment Reactor Using Computational Fluid Dynamics
,”
Appl. Biochem. Biotechnol.
,
130
(1–3), pp.
621
630
.10.1385/ABAB:130:1:621
22.
Zhu
,
G.
,
Tan
,
W.
,
Yu
,
Y.
, and
Liu
,
L.
,
2013
, “
Experimental and Numerical Study of the Solid Concentration Distribution in a Horizontal Screw Decanter Centrifuge
,”
Ind. Eng. Chem. Res.
,
52
(
48
), pp.
17249
17256
.10.1021/ie401902m
23.
Xiong
,
Q.
,
Kong
,
S.-C.
, and
Passalacqua
,
A.
,
2013
, “
Development of a Generalized Numerical Framework for Simulating Biomass Fast Pyrolysis in Fluidized-Bed Reactors
,”
Chem. Eng. Sci.
,
99
, pp.
305
313
.10.1016/j.ces.2013.06.017
24.
Wang
,
J.
,
2009
, “
A Review of Eulerian Simulation of Geldart A Particles in Gas-Fluidized Beds
,”
Ind. Eng. Chem. Res.
,
48
(
12
), pp.
5567
5577
.10.1021/ie900247t
25.
Xiong
,
Q.
,
Li
,
B.
,
Zhou
,
G.
,
Fang
,
X.
,
Xu
,
J.
,
Wang
,
J.
,
He
,
X.
,
Wang
,
X.
,
Wang
,
L.
,
Ge
,
W.
, and
Li
,
J.
,
2012
, “
Large-Scale DNS of Gas–Solid Flows on Mole-8.5
,”
Chem. Eng. Sci.
,
71
, pp.
422
430
.10.1016/j.ces.2011.10.059
26.
Xiong
,
Q.
,
Li
,
B.
,
Xu
,
J.
,
Wang
,
X.
,
Wang
,
L.
, and
Ge
,
W.
,
2012
, “
Efficient 3D DNS of Gas–Solid Flows on Fermi GPGPU
,”
Comput. Fluids
,
70
, pp.
86
94
.10.1016/j.compfluid.2012.08.026
27.
Xiong
,
Q.
,
Li
,
B.
,
Chen
,
F.
,
Ma
,
J.
,
Ge
,
W.
, and
Li
,
J.
,
2010
, “
Direct Numerical Simulation of Sub-Grid Structures in Gas–Solid Flow—GPU Implementation of Macro-Scale Pseudo-Particle Modeling
,”
Chem. Eng. Sci.
,
65
(
19
), pp.
5356
5365
.10.1016/j.ces.2010.06.035
28.
Xu
,
Y.
,
Padding
,
J.
,
van der Hoef
,
M.
, and
Kuipers
,
J.
,
2013
, “
Detailed Numerical Simulation of an Intruder Impacting on a Granular Bed Using a Hybrid Discrete Particle and Immersed Boundary (DP-IB) Method
,”
Chem. Eng. Sci.
,
104
, pp.
201
207
.10.1016/j.ces.2013.09.023
29.
Li
,
T.
,
Gopalakrishnan
,
P.
,
Garg
,
R.
, and
Shahnam
,
M.
,
2012
, “
CFD–DEM Study of Effect of Bed Thickness for Bubbling Fluidized Beds
,”
Particuology
,
10
(
5
), pp.
532
541
.10.1016/j.partic.2012.02.006
30.
Mullin
,
W.
, and
Ragan
,
R.
,
2005
, “
Derivation of Transverse Spin-Wave Dynamics From a Kinetic Equation in a Rotating Reference Frame
,”
J. Low Temp. Phys.
,
138
(
1–2
), pp.
73
78
.10.1007/s10909-005-1530-x
31.
Dallen
,
L.
, and
Neuenschwander
,
D. E.
,
2011
, “
Noether's Theorem in a Rotating Reference Frame
,”
Am. J. Phys.
,
79
(
3
), pp.
326
332
.10.1119/1.3535582
32.
Lun
,
C. K. K.
,
Savage
,
S. B.
,
Jeffrey
,
D. J.
, and
Chepurniy
,
N.
,
1984
, “
Kinetic Theories for Granular Flow: Inelastic Particles in Couette Flow and Slightly Inelastic Particles in a General Flow Field
,”
J. Fluid Mech.
,
140
, pp.
223
256
.10.1017/S0022112084000586
33.
Gidaspow
,
D.
,
1994
,
Multiphase Flow and Fluidization: Continuum and Kinetic Theory Descriptions
,
Academic Press
,
New York
.
34.
Gunn
,
D.
,
1978
, “
Transfer of Heat or Mass to Particles in Fixed and Fluidised Beds
,”
Int. J. Heat Mass Transfer
,
21
(
4
), pp.
467
476
.10.1016/0017-9310(78)90080-7
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