Heat exchangers are the important parts in thermoacoustic refrigerators. Types and configurations of the heat exchangers affect flow behaviors through stacks, and heat transfer behaviors between working fluids and the heat exchangers. Steady-flow heat transfer correlations to design a heat exchanger are not suitable for the thermoacoustic refrigerators due to their oscillatory flow conditions in resonator tubes. In this paper, a heat transfer correlation for a spiral-coil heat exchanger is presented. The results from the experimental study were used to develop an empirical equation between the Colburn-j factor, the Prandtl number, and the Reynolds number to correlate the oscillating heat transfer coefficient at the spiral-coil heat exchangers. The results showed that using steady-flow heat transfer correlations for analyses and design of the heat exchanger could result in distinguished errors. The heat transfer correlations developed for oscillatory flows on fin heat exchangers are also not suitable to predict heat transfer coefficients for spiral-coil heat exchanger due to difference in flow behaviors on the heat transfer surface. For oscillatory flows, the heat transfer coefficients can be improved by using curved-liked surface such as spiral coil instead of straightlike surface such as fin coil. The relationships between the oscillating heat transfer coefficients at the heat exchangers, drive ratios, and operating frequencies are also presented. Higher drive ratios and operating frequency result in greater heat transfer coefficients.

References

References
1.
Swift
,
G. W.
,
2002
,
Thermoacoustics: A Unified Perspective for Some Engines and Refrigerators
,
Acoustical Society of America Through the American Institute of Physics
,
Los Alamos, NM
.
2.
Swift
,
G. W.
,
1988
, “
Thermoacoustic Engines
,”
J. Acoust. Soc. Am.
,
84
(
4
), pp.
1145
1180
.10.1121/1.396617
3.
Tijani
,
M. E. H.
,
Zeegers
,
J. C. H.
, and
de Waele
,
A. T. A. M.
,
2002
, “
Design of Thermoacoustic Refrigerators
,”
Cryogenics
,
42
(
1
), pp.
49
57
.10.1016/S0011-2275(01)00179-5
4.
Akhavanbazaz
,
M.
,
Siddiqui
,
M. H. K.
, and
Bhat
,
R. B.
,
2007
, “
The Impact of Gas Blockage on the Performance of a Thermoacoustic Refrigerator
,”
Exp. Therm. Fluid Sci.
,
32
(
1
), pp.
231
239
.10.1016/j.expthermflusci.2007.03.009
5.
Wantha
,
C.
, and
Assawamartbunlue
,
K.
,
2011
, “
The Impact of the Resonance Tube on Performance of a Thermoacoustic Stack
,”
Front. Heat Mass Transfer
,
2
(
4
), pp.
1
8
.10.5098/hmt.v2.4.3006
6.
Hofler
,
T. J.
,
1986
, “
Thermoacoustic Refrigerator Design and Performance
,” Ph.D. thesis, University of California, San Diego, CA.
7.
Tu
,
Q.
,
Gusev
,
V.
,
Bruneau
,
M.
,
Zhang
,
C.
,
Zhao
,
L.
, and
Guo
,
F.
,
2005
, “
Experimental and Theoretical Investigation on Frequency Characteristic of Loudspeaker-Driven Thermoacoustic Refrigerator
,”
Cryogenics
,
45
(
12
), pp.
739
746
.10.1016/j.cryogenics.2005.09.004
8.
Wantha
,
C.
, and
Assawamartbunlue
,
K.
,
2013
, “
Experimental Investigation of the Effects of Driver Housing and Resonance Tube on the Temperature Difference across a Thermoacoustic Stack
,”
Heat Mass Transfer
,
49
(
6
), pp.
887
896
.10.1007/s00231-013-1150-y
9.
Tijani
,
M. E. H.
,
2001
, “
Loudspeaker-Driven Thermo-Acoustic Refrigeration
,” Ph.D. thesis, Eindhoven University of Technology, Eindhoven, Netherlands.
10.
Wetzel
,
M.
, and
Herman
,
C.
,
1997
, “
Design Optimization of Thermoacoustic Refrigerators
,”
Int. J. Refrig.
,
20
(
1
), pp.
3
21
.10.1016/S0140-7007(96)00064-3
11.
Wetzel
,
M.
, and
Herman
,
C.
,
1999
, “
Experimental Study of Thermoacoustic Effects on a Single Plate Part 2: Heat Transfer
,”
Heat Mass Transfer
,
35
(
6
), pp.
433
441
.10.1007/s002310050345
12.
Wetzel
,
M.
, and
Herman
,
C.
,
2000
, “
Experimental Study of Thermoacoustic Effects on a Single Plate Part I: Temperature Fields
,”
Heat Mass Transfer
,
36
(
1
), pp.
7
20
.10.1007/s002310050358
13.
Nsofor
,
E. C.
,
Celik
,
S.
, and
Wang
,
X.
,
2007
, “
Experimental Study on the Heat Transfer at the Heat Exchanger of the Thermoacoustic Refrigerating System
,”
Appl. Therm. Eng.
,
27
(
14–15
), pp.
2435
2442
.10.1016/j.applthermaleng.2007.03.008
14.
Paek
,
I.
,
2005
, “
Performance Characterization of Thermoacoustic Cooler Components and Systems
,” Ph.D. thesis, Purdue University, West Lafayette, IN.
15.
Poese
,
M. E.
, and
Garret
,
S. L.
,
2000
, “
Performance Measurements on a Thermoacoustic Refrigerator Driven at High Amplitudes
,”
J. Acoust. Soc. Am.
,
107
(
5
), pp.
2480
2486
.10.1121/1.428635
16.
Mozurkewich
,
G.
,
2001
, “
Heat Transfer From Transverse Tubes Adjacent to a Thermoacoustic Stack
,”
J. Acoust. Soc. Am.
,
110
(
2
), pp.
841
847
.10.1121/1.1385180
17.
Incropera
,
F. P.
,
Dewitt
,
D. P.
,
Bergman
,
T. L.
, and
Lavine
,
A. S.
,
2013
,
Foundations of Heat Transfer
,
John Wiley & Sons
,
Singapore
.
18.
Paek
,
I.
,
Braun
,
J. E.
, and
Mongeau
,
L.
,
2005
, “
Characterizing Heat Transfer Coefficients for Heat Exchangers in Standing Wave Thermoacoustic Coolers
,”
J. Acoust. Soc. Am.
,
118
(
4
), pp.
2271
2280
.10.1121/1.2019425
19.
Holman
,
J. P.
,
2001
,
Experimental Methods for Engineers
,
McGraw-Hill Higher Education
,
Singapore
.
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