Frost on heat exchanger fin surfaces increases the thermal resistance and blocks the air flow passages, which reduce the system energy efficiency. Therefore, investigations of frost formation especially simulations of frosting on the heat exchanger surfaces are essential for designing heat exchangers that operate with frosting. In this paper, the frost growth and densification processes on fin-and-tube heat exchanger surfaces are numerically investigated using a mass transfer model implemented as a user-defined function (UDF) in fluent. The model predicts the frost distributions on the heat exchanger surfaces, the temperature distributions, and the air flow pressure drop. The results show that the frost is thicker and the frost density is higher on the fin surfaces on the windward side near the tubes, while the frost is thinner and the density is lower near the inlet. Very little frost appears in the tube wake region. Frost on the fin-and-tube heat exchanger surfaces restricts the airflow and about doubles the pressure drop after frosting for 50 min. The simulated frost distributions and pressure drops are in good agreement with experimental data, which means that the frosting model can be used to predict frost layer growth on heat exchanger surfaces and the resulting airflow resistance.

References

References
1.
Wu
,
X. M.
, and
Webb
,
R. L.
,
2001
, “
Investigation of the Possibility of Frost Release From a Cold Surface
,”
Exp. Therm. Fluid Sci.
,
24
(
3–4
), pp.
151
156
.
2.
Wu
,
X. M.
,
Dai
,
W.
,
Xu
,
W.
, and
Tang
,
L.
,
2007
, “
Mesoscale Investigation of Frost Formation on a Cold Surface
,”
Exp. Therm. Fluid Sci.
,
31
(
8
), pp.
1043
1048
.
3.
Wu
,
X. M.
,
Dai
,
W.
,
Shan
,
X.
,
Wang
,
W.
, and
Tang
,
L.
,
2007
, “
Visual and Theoretical Analyses of the Early Stage of Frost Formation on Cold Surfaces
,”
J. Enhanced Heat Transfer
,
14
(
3
), pp.
257
268
.
4.
Wu
,
X. M.
,
Hu
,
S.
, and
Chu
,
F.
,
2016
, “
Experimental Study of Frost Formation on Cold Surfaces With Various Fin Layouts
,”
Appl. Therm. Eng.
,
95
, pp.
95
105
.
5.
Wu
,
X. M.
,
Ma
,
Q.
,
Chu
,
F.
, and
Hu
,
S.
,
2016
, “
Phase Change Mass Transfer Model for Frost Growth and Densification
,”
Int. J. Heat Mass Transfer
,
96
, pp.
11
19
.
6.
O'Neal
,
D. L.
, and
Tree
,
D. R.
,
1984
, “
Measurement of Frost Growth and Density in a Parallel Plate Geometry
,”
ASHRAE Trans.
,
90
, pp.
278
290
.
7.
Na
,
B.
, and
Webb
,
R. L.
,
2004
, “
New Model for Frost Growth Rate
,”
Int. J. Heat Mass Transfer
,
47
(
5
), pp.
925
936
.
8.
Lee
,
K. S.
,
Jhee
,
S.
, and
Yang
,
D. K.
,
2003
, “
Prediction of the Frost Formation on a Cold Flat Surface
,”
Int. J. Heat Mass Transfer
,
46
(
20
), pp.
3789
3796
.
9.
Yao
,
Y.
,
Jiang
,
Y.
,
Deng
,
S.
, and
Ma
,
Z.
,
2004
, “
A Study on the Performance of the Airside Heat Exchanger Under Frosting in an Air Source Heat Pump Water Heater/Chiller Unit
,”
Int. J. Heat Mass Transfer
,
47
(
17–18
), pp.
3745
3756
.
10.
Lee
,
Y. B.
, and
Ro
,
S. T.
,
2005
, “
Analysis of the Frost Growth on a Flat Plate by Simple Models of Saturation and Supersaturation
,”
Exp. Therm. Fluid Sci.
,
29
(
6
), pp.
685
696
.
11.
Lee
,
K. S.
,
Kim
,
W. S.
, and
Lee
,
T. H.
,
1997
, “
A One-Dimensional Model for Frost Formation on a Cold Flat Surface
,”
Int. J. Heat Mass Transfer
,
40
(
18
), pp.
4359
4365
.
12.
Na
,
B.
, and
Webb
,
R. L.
,
2004
, “
Mass Transfer On and Within a Frost Layer
,”
Int. J. Heat Mass Transfer
,
47
(
5
), pp.
899
911
.
13.
Kandula
,
M.
,
2011
, “
Frost Growth and Densification in Laminar Flow Over Flat Surfaces
,”
Int. J. Heat Mass Transfer
,
54
(
15–16
), pp.
3719
3731
.
14.
Yang
,
D. K.
, and
Lee
,
K. S.
,
2005
, “
Modeling of Frosting Behavior on a Cold Plate
,”
Int. J. Refrig.
,
28
(
3
), pp.
396
402
.
15.
Yang
,
D. K.
,
Lee
,
K. S.
, and
Cha
,
D. J.
,
2006
, “
Frost Formation on a Cold Surface Under Turbulent Flow
,”
Int. J. Refrig.
,
29
(
2
), pp.
164
169
.
16.
Lenic
,
K.
,
Trp
,
A.
, and
Frankovic
,
B.
,
2009
, “
Transient Two-Dimensional Model of Frost Formation on a Fin-and-Tube Heat Exchanger
,”
Int. J. Heat Mass Transfer
,
52
(
1–2
), pp.
22
32
.
17.
Lenic
,
K.
,
Trp
,
A.
, and
Frankovic
,
B.
,
2009
, “
Prediction of an Effective Cooling Output of the Fin-and-Tube Heat Exchanger Under Frosting Conditions
,”
Appl. Therm. Eng.
,
29
(
11–12
), pp.
2534
2543
.
18.
Armengol
,
J. M.
,
Salinas
,
C. T.
,
Xaman
,
J.
, and
Ismail
,
K. A. R.
,
2016
, “
Modeling of Frost Formation Over Parallel Cold Plates Considering a Two-Dimensional Growth Rate
,”
Int. J. Therm. Sci.
,
104
, pp.
245
256
.
19.
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
(
9
), pp.
305
313
.
20.
Xiong
,
Q.
,
Aramideh
,
S.
,
Passalacqua
,
A.
, and
Kong
,
S. C.
,
2015
, “
Characterizing Effects of the Shape of Screw Conveyors in Gas–Solid Fluidized Beds Using Advanced Numerical Models
,”
ASME J. Heat Transfer
,
137
(
6
), p.
061008
.
21.
Xiong
,
Q.
, and
Kong
,
S. C.
,
2014
, “
Modeling Effects of Interphase Transport Coefficients on Biomass Pyrolysis in Fluidized Beds
,”
Powder Technol.
,
262
, pp.
96
105
.
22.
Cui
,
J.
,
Li
,
W. Z.
,
Liu
,
Y.
, and
Jiang
,
Z. Y.
,
2011
, “
A New Time- and Space-Dependent Model for Predicting Frost Formation
,”
Appl. Therm. Eng.
,
31
(
4
), pp.
447
457
.
23.
Kim
,
D.
,
Kim
,
C.
, and
Lee
,
K. S.
,
2015
, “
Frosting Model for Predicting Macroscopic and Local Frost Behaviors on a Cold Plate
,”
Int. J. Heat Mass Transfer
,
82
, pp.
135
142
.
24.
Cui
,
J.
,
Li
,
W. Z.
,
Liu
,
Y.
, and
Zhao
,
Y. S.
,
2011
, “
A New Model for Predicting Performance of Fin-and-Tube Heat Exchanger Under Frost Condition
,”
Int. J. Heat Fluid Flow
,
32
(
1
), pp.
249
260
.
25.
Kwon
,
J. T.
,
Lim
,
H. J.
,
Kwon
,
Y. C.
,
Koyama
,
S.
,
Kim
,
D. H.
, and
Kondou
,
C.
,
2006
, “
An Experimental Study on Frosting of Laminar Air Flow on a Cold Surface With Local Cooling
,”
Int. J. Refrig.
,
29
(
5
), pp.
754
760
.
26.
ASHRAE
,
2001
,
2001 ASHRAE Handbook-Fundamentals
,
The American Society of Heating, Refrigerating and Air-Conditioning Engineers
,
Atlanta, GA
, Chap. 6.
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