Stationary spiral inserts can effectively enhance heat transfer and temperature blending in the heat convection systems. In this paper, the impact of the segment length on the performance of a stationary insert is studied for flow Re numbers from 80 to 7900 through numerical simulation of heat transfer in streams of cold and hot gases flowing across it. The segment length to width ratio is from 1.11 to 2.33. The temperature of the studied gas is from 300 K to 1300 K. It is shown that the insert with variable segment length is more effective in temperature blending for two compressible streams compared with an insert with constant segment length, especially for low-Re-number turbulent flows.

1.
Rahmani
,
R. K.
,
Keith
,
T. G.
, and
Ayasoufi
,
A.
, 2006, “
Numerical Study of the Heat Transfer Rate in a Helical Static Mixer
,”
ASME J. Heat Transfer
0022-1481,
128
(
8
), pp.
769
783
.
2.
Joshi
,
P.
,
Nigam
,
K. D. P.
, and
Nauman
,
E. B.
, 1995, “
The Kenics Static Mixer: New Data and Proposed Correlations
,”
Chem. Eng. J.
0300-9467,
59
, pp.
265
271
.
3.
Shah
,
N. F.
, and
Kale
,
D. D.
, 1991, “
Pressure Drop for Laminar Flow of Non-Newtonian Fluids in Static Mixers
,”
Chem. Eng. Sci.
0009-2509,
46
, pp.
2159
2161
.
4.
Chandra
,
K. G.
, and
Kale
,
D. D.
, 1992, “
Pressure Drop for Laminar Flow of Viscoelastic Fluids in Static Mixers
,”
Chem. Eng. Sci.
0009-2509,
47
, pp.
2097
2100
.
5.
Xu
,
G.
,
Feng
,
L.
,
Li
,
Y.
, and
Wang
,
K.
, 1997, “
Pressure Drop of Pseudo-Plastic Fluids in Static Mixers
,”
Chin. J. Chem. Eng.
1004-9541,
5
(
1
), pp.
93
96
.
6.
Pahl
,
M. H.
, and
Muschelknautz
,
E.
, 1982, “
Static Mixers and Their Applications
,”
Int. Chem. Eng.
0020-6318,
22
, pp.
197
204
.
7.
Boss
,
J.
, and
Czastkiewicz
,
W.
, 1982, “
Principles of Scale-Up for Laminar Mixing Process of Newtonian Fluids in Fluids in Static Mixer
,”
Int. Chem. Eng.
0020-6318,
22
, pp.
362
367
.
8.
Morris
,
W. D.
, and
Misson
,
P.
, 1974, “
An Experimental Investigation of Mass Transfer and Flow Resistance in the Kenics Static Mixer
,”
Ind. Eng. Chem. Process Des. Dev.
0196-4305,
13
, pp.
270
275
.
9.
Middleman
,
S.
, 1974, “
Drop Size Distributions Produced by Turbulent Pipe Flow of Immiscible Fluids Through a Static Mixer
,”
Ind. Eng. Chem. Process Des. Dev.
0196-4305,
13
, pp.
78
83
.
10.
Morris
,
W. D.
, and
Proctor
,
R.
, 1977, “
The Effect of Twist Ration on Forced Convection in the Kenics Static Mixer
,”
Ind. Eng. Chem. Process Des. Dev.
0196-4305,
16
, pp.
406
412
.
11.
Li
,
H. Z.
,
Fasol
,
C.
, and
Choplin
,
L.
, 1996, “
Hydrodynamics and Heat Transfer of Rheologically Complex Fluids in a Sulzer SMX Static Mixer
,”
Chem. Eng. Sci.
0009-2509,
51
(
10
), pp.
1947
1955
.
12.
Qi
,
Y.
,
Kawaguchi
,
Y.
,
Christensen
,
R. N.
, and
Zakin
,
J. L.
, 2003, “
Enhancing Heat Transfer Ability of Drag Reducing Surfactant Solutions With Static Mixers and Honeycombs
,”
Int. J. Heat Mass Transfer
0017-9310,
46
, pp.
5161
5173
.
13.
Lang
,
E.
,
Drtina
,
P.
,
Streiff
,
F.
, and
Fleishli
,
M.
, 1995, “
Numerical Simulation of the Fluid Flow and the Mixing Process in a Static Mixer
,”
Int. J. Heat Mass Transfer
0017-9310,
38
(
12
), pp.
2239
2250
.
14.
Visser
,
J. E.
,
Rozendal
,
P. F.
,
Hoogstraten
,
H. W.
, and
Beenackers
,
A. A. C. M.
, 1999, “
Three-Dimensional Numerical Simulation of Flow and Heat Transfer in the Sulzer SMX Static Mixer
,”
Chem. Eng. Sci.
0009-2509,
54
, pp.
2491
2500
.
15.
Rahmani
,
R. K.
,
Ayasoufi
,
A.
, and
Keith
,
T. G.
, 2007, “
A Numerical Study of the Global Performance of Two Static Mixers
,”
ASME J. Fluids Eng.
0098-2202,
129
(
3
), pp.
338
349
.
16.
Khakhar
,
D. V.
,
Franjione
,
J. G.
, and
Ottino
,
J. M.
, 1987, “
A Case Study of Chaotic Mixing in Deterministic Flows: The Partitioned-Pipe Mixer
,”
Chem. Eng. Sci.
0009-2509,
42
, pp.
2909
2926
.
17.
Kusch
,
H. A.
, and
Ottino
,
J. M.
, 1992, “
Experiments on Mixing in Continuous Chaotic Flows
,”
J. Fluid Mech.
0022-1120,
236
, pp.
319
348
.
18.
Hobbs
,
D. M.
, and
Muzzio
,
F. J.
, 1998, “
Reynolds Number Effects on Laminar Mixing in the Kenics Static Mixer
,”
Chem. Eng. J.
0300-9467,
70
, pp.
93
104
.
19.
Rahmani
,
R. K.
,
Keith
,
T. G.
, and
Ayasoufi
,
A.
, 2008, “
Numerical Simulation of Turbulent Flow in an Industrial Helical Static Mixer
,”
Int. J. Numer. Methods Heat Fluid Flow
0961-5539,
18
, pp.
675
696
.
20.
Byrde
,
O.
, and
Sawley
,
M. L.
, 1999, “
Optimization of a Kenics Static Mixer for Non-Creeping Flow Conditions
,”
Chem. Eng. J.
0300-9467,
72
, pp.
163
169
.
21.
Byrde
,
O.
, and
Sawley
,
M. L.
, 1999, “
Parallel Computation and Analysis of the Flow in a Static Mixer
,”
Comput. Fluids
0045-7930,
28
, pp.
1
18
.
22.
Incropera
,
F. P.
,
Dewitt
,
D. P.
,
Bergman
,
T. L.
, and
Lavine
,
A. S.
, 2007,
Introduction to Heat Transfer
, 5th ed.,
Wiley
,
New York
.
23.
Sotiropoulos
,
F.
, and
Patel
,
V. C.
, 1995, “
On the Role of Turbulence Anisotropy and Near-Wall Modeling in Predicting Three-Dimensional Shear-Flows
,”
AIAA J.
0001-1452,
33
, pp.
504
514
.
24.
Sotiropoulos
,
F.
, and
Ventikos
,
Y.
, 1998, “
Flow Through a Curved Duct Using Nonlinear Two-Equation Turbulence Model
,”
AIAA J.
0001-1452,
36
, pp.
1256
1262
.
25.
Lin
,
F. B.
, and
Sotiropoulos
,
F.
, 1997, “
Strongly-Coupled Multigrid Method for 3-D Incompressible Flows Using Near-Wall Turbulence Closures
,”
J. Fluid Mech.
0022-1120,
119
, pp.
314
324
.
26.
Rahmani
,
R. K.
,
Keith
,
T. G.
, and
Ayasoufi
,
A.
, 2005, “
Three-Dimensional Numerical Simulation and Performance Study of an Industrial Helical Static Mixer
,”
ASME J. Fluids Eng.
0098-2202,
127
(
3
), pp.
467
483
.
27.
Jones
,
S. C.
, 1999, “
Static Mixers for Water Treatment
,” Ph.D. thesis, Georgia Institute of Technology, Atlanta, GA.
28.
Rahmani
,
R. K.
,
Keith
,
T. G.
, and
Ayasoufi
,
A.
, 2004, “
Large-Eddy Turbulent Flow Simulation Flow of an Industrial Helical Static Mixer
,”
Proceedings of the 2004 ASME Heat Transfer/Fluid Engineering Summer Conference
, Charlotte, NC, Jul. 11–15.
29.
Thompson
,
J. F.
,
Soni
,
B. K.
, and
Weatherill
,
N. P.
, 1999,
Handbook of Grid Generation
,
CRC
,
Boca Raton, FL
.
30.
Warming
,
R. F.
, and
Beam
,
R. M.
, 1976, “
Upwind Second-Order Difference Schemes and Applications in Unsteady Aerodynamic Flows
,”
AIAA J.
0001-1452,
14
(
9
), pp.
1241
1249
.
31.
Barth
,
T. J.
, and
Jespersen
,
D.
, 1989, “
The Design and Application of Upwind Schemes on Unstructured Meshes
,”
AIAA 27th Aerospace Sciences Meeting
, Reno, NV, Paper No. AIAA-89-0366.
32.
Van Doormaal
,
J. P.
, and
Raithby
,
G. D.
, 1984, “
Enhancements of the SIMPLE Method for Predicting Incompressible Fluid Flows
,”
Numer. Heat Transfer
0149-5720,
7
, pp.
147
163
.
33.
Rahmani
,
R. K.
,
Tanbour
,
E. Y.
,
Ayasoufi
,
A.
, and
Molavi
,
H.
, 2010, “
Enhancement of Convective Heat Transfer in Internal Compressible Flows by Stationary Inserts
,”
J. Thermal Sci. Eng. Appl.
1948-5085,
2
(
1
), p.
011005
.
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