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An Experimental Investigation on Friction
Characteristics and Heat Transfer of Air and CO2 Flow
in Microtubes With Structured Surface Roughness
a
b
b
Ting-Yu Lin , Chia-Wei Chen , Chien-Yuh Yang & Satish G. Kandlikar
a
a
Mechanical Engineering Department , Rochester Institute of Technology , Rochester , New
York , USA
b
Mechanical Engineering Department , National Central University , Jhong-Li , Taoyuan ,
Taiwan
Accepted author version posted online: 26 Jun 2013.Published online: 05 Sep 2013.
To cite this article: Ting-Yu Lin , Chia-Wei Chen , Chien-Yuh Yang & Satish G. Kandlikar (2014) An Experimental Investigation
on Friction Characteristics and Heat Transfer of Air and CO2 Flow in Microtubes With Structured Surface Roughness, Heat
Transfer Engineering, 35:2, 150-158, DOI: 10.1080/01457632.2013.812485
To link to this article: http://dx.doi.org/10.1080/01457632.2013.812485
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Heat Transfer Engineering, 35(2):150–158, 2014
C Taylor and Francis Group, LLC
Copyright ISSN: 0145-7632 print / 1521-0537 online
DOI: 10.1080/01457632.2013.812485
An Experimental Investigation on
Friction Characteristics and Heat
Transfer of Air and CO 2 Flow
in Microtubes With Structured
Surface Roughness
TING-YU LIN,1 CHIA-WEI CHEN,2 CHIEN-YUH YANG,2
and SATISH G. KANDLIKAR1
1
2
Mechanical Engineering Department, Rochester Institute of Technology, Rochester, New York, USA
Mechanical Engineering Department, National Central University, Jhong-Li, Taoyuan, Taiwan
Experiments were conducted to investigate roughness effects on flow characteristics and heat transfer of air and CO2 flow
in four circular micr-tubes of approximately 1 mm inner diameter. The tubes were made by electrodepositing nickel on an
aluminum sacrificial substrate. The desired roughness structures were machined or etched on the substrate before depositing
nickel to generate a replica of the aluminum substrate on the internal surface of the nickel tubes. Four different surface
roughness features were generated: (i) uniform roughness of 3.8 µm, (ii) uniform roughness of 1.8 µm, (iii) internal grooves
45 µm deep and 218 µm wide, and (iv) helical grooves 96 µm deep with 1.9 mm pitch. Friction factor and Nusselt number
data for the smooth tube are in good agreement with the conventional correlations in both the laminar and the turbulent flow
regimes. In the rough tubes, the friction factors are significantly higher than that of the smooth tube. Heat transfer coefficients
in the laminar flow regime for both smooth and rough tube agree well with the conventional correlation. However, in the
turbulent flow regime, heat transfer was enhanced by the roughness features and the enhancement increased with increasing
Reynolds number.
INTRODUCTION
Heat transfer and flow characteristics in microchannels have
been widely studied in support of the developments in microelectromechanical systems (MEMS) technology and their application in micro heat exchangers, fuel cells, biomedical chips, and
other microscale devices requiring thermal control. Many earlier
publications indicated that the heat transfer and flow characteristics in microchannels are not in agreement with the predictions
from the conventional correlations for smooth channels [1–6].
It is gratefully acknowledged that the financial support for this work was
provided by the National Science Council (NSC 98-2221-E-008-088-MY3),
Taiwan, and U.S. National Science Foundation (CBET-0829038).
Address correspondence to Professor Chien-Yuh Yang, Mechanical Engineering Department National Central University, No. 300, Jhong-Da Road, 320
Jhong-Li, Taoyuan, Taiwan. E-mail: [email protected]
However, subsequent research indicated that for liquid flow in
circular smooth microtubes, friction factors and heat transfer
coefficients were in agreement with the conventional correlations [7–11]. The experimental data were predicted well by the
conventional correlations for tubes with diameters larger than
15 μm [7] for friction factor and 123 μm [8] for Nusselt number.
Friction factors in mini- and microscale rough channels
were systematically investigated by Kandlikar [12], Brackbill
and Kandlikar [13, 14], and Kandlikar et al. [15]. The effects of
the roughness element height, pitch, and relative roughness on
friction factor were studied experimentally. Their data showed
that the friction factors in smooth channels were in good
agreement with the conventional correlations, while in rough
channels the friction factors were significantly higher than the
predictions from the smooth channel correlations. A model
was proposed to predict the early transition from laminar to
turbulent flow due to roughness effects [14, 15]. A constricted
hydraulic diameter was defined for use in rough channels by
150
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T.-Y. LIN ET AL.
considering the minimum flow area in a channel. Previous
researchers also studied the roughness effect on gas flow in
microchannels. The experimental data of [16] revealed that the
friction factors in smooth channels were in good agreement with
the predictions from the smooth channel correlations; however,
in rough tubes the friction factor was reported to be higher than
the predictions. Circular tubes with different internal surface
roughness structures were studied by Kandlikar et al. [17]. The
Ra /di in their study ranged from 0.36% to 0.16% for a 0.62-mm
tube and 0.18% to 0.28% for a 1.067-mm tube. Heat transfer
enhancement due to roughness was observed in their work.
Heat transfer enhancement in both laminar and turbulent
flows has been an area of great interest [18]. In macroscale
laminar flows, some of the enhancement techniques receiving
renewed interest are twisted tubes [19, 20], porous materials
[21], and coiled wires [22]. In turbulent flow, enhanced structures on the internal channel walls were investigated and found
to enhance heat transfer. Pethkool et al. [23] investigated heat
transfer enhancement in a helically corrugated tube. Their data
showed that the effect of relative roughness was higher than the
effect of pitch. There are very limited data available showing
systematic effects of enhancement techniques on heat transfer
and pressure drop.
Very few researchers have investigated heat transfer of gas
flow in microchannels due to the difficulties in conducting
such experiments at microscale. This research aimed at making
roughness structures on the internal surface of a circular tube
using an electrodepositing technique, and testing them with gas
flow to obtain their fluid flow and heat transfer characteristics.
Experiments on smooth tubes in the same diameter range were
also performed in order to compare the effect of roughness on
friction factor and Nusselt number. The process of fabricating
rough tubes, experimental setup details, and experimental results for friction factors and Nusselt numbers are discussed in
detail in the following section.
EXPERIMENTAL METHOD
Fabrication of Internally Roughened Tubes
151
Figure 1 Processes for fabricating internally roughened nickel tubes: (a) sacrificial substrate, (b) roughstructure machining on the substrate, (c) nickel layer
deposition on the roughened substrate, and (d) substrate removal. (Color figure
available online.)
b. Rough structure machining: For the random roughness surface tubes, the rough surfaces on the substrate tube were
scraped by number 50 and number 120 sandpapers. The images of the external surface of the substrate tubes after scraping were taken by a laser confocal microscope and are shown
in Figure 2. The surface roughness of the aluminum tubes,
Ra , after scraping by number 50 and number 120 sandpapers
were measured as 9.3 μm and 5.6 μm, respectively.
Two methods were used to generate structured roughness
surfaces. One is by machining the substrate tube directly
as shown in Figure 3a. The depth and pitch of the grooves
are 45 μm and 220 μm, respectively. The other method
involved etching the substrate tube. First, the substrate tube
was wrapped with polytetrafluoroethylene (PTFE) tape to
expose only the groove region, which was then etched away
by an NaOH solution. The substrate tube region covered
by PTFE tape was not etched, while the open surface was
etched to form helical grooves on the tube as shown in Figure
3b. The groove depth and pitch are 96 μm and 1.9 mm,
respectively.
c. Nickel layer deposition: Nickel was electrically deposited
on the outer surface of the roughened substrate tube. The
thickness of the Ni layer was approximately 120 μm. Nickel
was selected for its relatively high electricity resistance, good
thermal conductivity, hardness, and strength.
d. Substratum removal: A 10% NaOH solution at 50◦ C was
pumped through the aluminum sacrificial tube coated
with nickel. The aluminum was removed by the solution
and a nickel tube with internal rough surface structure
The fabrication process to produce different internal roughness surfaces tubes included four steps as illustrated in Figure 1:
(a) the choice of sacrificial substrate material, (b) preparing
rough structures on the substrate surface, (c) nickel layer deposition, and (d) removal of sacrificial substrate. The details are
described as follows:
a. Sacrificial substrate material selection: Aluminum tubes with
inner and outer diameters of 0.5 mm and 1.0 mm, respectively, were selected as the sacrificial substrate for all nickel
tubes fabricated. Aluminum was selected for its easy machinability and ease in removing the material by etching after
deposition of nickel.
heat transfer engineering
Figure 2 External surface of aluminum substrate for random roughness surface tubes: (a) scraped by number 50 sandpaper, (b) scraped by number 120
sandpaper.
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T.-Y. LIN ET AL.
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Figure 3 External surface of aluminum sacrificial substrate for structured
surface tubes: (a) direct machining, (b) etched with Teflon masking tape wrap.
(Color figure available online.)
was obtained. The cross-sectional image of the aluminum
substrate tube with nickel deposited on it is shown in Figure
4a. Nickel is uniformly deposited on the aluminum tube.
The rough nickel tube after removing aluminum substrate is
shown in Figure 4b.
Internal Surfaces Profile of Tubes
The tubes were cut axially and images were taken and analyzed by a laser confocal microscope. Figure 5 shows the internal surface profiles of the test tubes presented in the form of a
two-dimensional (2-D) image, three-dimensional (3-D) contour
plot, and surface center line profile. Figure 5a is the commercial smooth stainless steel 304 tube termed as Tube A. Figures
5b and 5c are the random roughness surface tubes that were
generated from the substrate scraped by sandpaper number 50
and number 120 and termed Tube B and Tube C, respectively.
Figures 5d and 5e are structured roughness surface tubes which
were generated from the machined substrate and PTFE tapewrapped substrate with chemical etching and termed - Tube D
and Tube E, respectively.
In this study the internal surface roughness of the nickel tubes
is formed due to the nonuniform roughness
elements. Instead
of the average roughness, Ra (= 1n ni=1 |yi |), the roughness
level was also represented by Rc in the present study. Rc is the
mean value of the profile element heights with a sampling length
defined as follows:
n
1
Zti
(1)
Rc =
n i=1
Figure 4 Cross section of the nickel tube: (a) with sacrificial aluminum substrate, (b) with substrate removal. (Color figure available online.)
where Zti are the element heights as shown in Figure 6. The
detailed dimensions of the test tubes are listed in Table 1.
The inner diameters of the rough nickel tubes were measured
by laser confocal microscope at the two ends of the tube. For
smooth tubes, the internal tube diameter was measured by an
optical microscope (OM). The average tube diameter is calculated from the tube flow area of several individual cross-section
images.
Experimental System Setup
The schematic diagram of the test facility developed at RIT
is shown in Figure 7. It is the same as that described in Lin
and Kandlikar [24] and Yang et al. [25]. Pressurized air and
CO2 were used as the working fluids. High-pressure gas flows
through a regulator to the test section. A mass flowmeter was
connected between the regulator and the test section. The inlet gas temperature was measured by a resistance temperature
detector (RTD). DC power was supplied through the clamps
attached on the ends of the test tube to heat the tube wall. The
DC voltage and current were individually measured by ampere
and volt meters. The power input was obtained by the product of measured current and voltage. In addition to what is
shown in Figure 7, several thermocouples were attached on the
tube wall to measure the external wall temperatures. Internal
tube wall temperature was derived from the measured external wall temperature by using a one-dimensional, steady-state
heat conduction equation with heat generation [17]. Flow meters, thermocouples, pressure sensor, and power supply were
interfaced with the LabVIEW program to acquire the data. The
Table 1 Detail dimensions of the test tubes
Substratum
Surface
Treatment
Outer roughness
Pitch, P
Height, H
Test tube
di (μm)
dcf (μm)
L (mm)
Rc (μm)
Ra (μm)
A
Smooth
N/A
N/A
B
Rough
Number 50 sandpaper
Ra = 9.3 μm
C
Rough
Number 120 sandpaper
Ra = 5.3 μm
A
962
956
330
2.8
0.70
B
977
940
155
18.7
3.8
C
950
939
171
5.3
1.8
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vol. 35 no. 2 2014
D
groove
Dies
Rc = 45 μm
218 μm
45 μm
D
939
913
154
13.2
3.5
E
Helical groove
PTFE tape
Rc = 96 μm
1.9 mm
96 μm
E
990
901
160
44.6
13.7
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T.-Y. LIN ET AL.
153
Figure 5 Internal surface profiles of test tubes: (a) Tube A (smooth), (b) Tube B (roughened by number 50 sandpaper), (c) Tube C (roughened by number 50
sandpaper), (d) Tube D, circular grooves (using machined substrate), (e) Tube E, helical grooves (substrate roughened by PTFE tape wrapping and etching). (Color
figure available online.)
Figure 6 Dimensions of the profile element heights within a sampling length.
heat transfer engineering
experimental apparatus and derived parameter uncertainties are
listed in Table 2.
Heat loss is not negligible for gas flow in microtubes, due to
its low heat capacity and low heat transfer coefficient. The test
section was enclosed in a vacuum chamber with pressure below
13 mtorr to minimize heat loss. The heat loss for each tube as
a function of temperature was individually evaluated. The tube
was heated directly by the power supply and the applied power
was quantified as the heat loss. The test tube was heated inside
the vacuum chamber without working fluid flowing through it.
The applied power was treated as the heat loss. The maximum
heat loss to heat input ratio in the present study is lower than
12%.
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T.-Y. LIN ET AL.
Figure 7 Schematic of the experimental setup. (Color figure available online.)
Table 3
RESULTS AND DISCUSSION
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Friction Factor
Due to the compressibility of air and CO2 , the apparent friction factor was calculated from the correlation given by Shapiro
[26] as follows:
dh P2in − P2out
Pin
(2)
f=
−
2ln
L
Pout
RTG2
where dh , L, R, T, G, Pin , and Pout are the hydraulic diameter,
tube length, specific gas constant, fluid temperature, mass flux,
and inlet and outlet pressure of tubes, respectively. Figure 8
shows friction factor as a function of Reynolds number for CO2
and airflow in the smooth tube. It is observed that the friction
factor of CO2 and that of air are the same and can be predicted
very well by the conventional correlations in both laminar and
turbulent flow regimes. Details of the conventional correlations
used for estimating friction factors [27, 28] and heat transfer
coefficients [29, 30] are given in Table 3. The transition Re is
about 2000, which is similar to that for fluid flow in macroscale
tubes.
In smooth tubes, the internal diameter is used as the characteristic length. However, in rough tubes, the definition of tube
diameter will affect the friction factor and heat transfer results.
By considering the effect of cross-sectional area reduction due to
protruding roughness elements, constricted diameter dcf defined
by reference [15] was the same as the hydraulic diameter:
dh = dcf = di − 2Rc
Conventional correlations applied in the present study
Blasius equations [27]
f = 0.079Red −1/4
Filonenko [28]
f = (1.58 ln Red -3.28)−2
Petukhov [29]
Nud =
Gnielinski [30]
Nud =
(f/8)Red Pr
1.07+12.7(f/8)1/2 (Pr2/3 −1)
(f/8)(Red −1000)Pr
1+12.7(f/8)1/2 (Pr2/3 −1)
Figure 9 shows the comparison of friction factors of Tube E by
defining hydraulic diameter as di and dcf . The two data sets show
a higher friction factor than conventional correlations derived
from smooth tubes in both laminar and turbulent flow. By using
dcf as the hydraulic diameter, the data show a better prediction by
the conventional correlation. By using di as hydraulic diameter,
friction factor is higher than for conventional correlations, by
about 55–83% in laminar flow and 74–76% in turbulent flow.
By using dcf as hydraulic diameter, friction factor is higher than
for conventional correlations, by about 31–75% in laminar flow
and 58–59% in turbulent flow.
A conventional friction factor correlation for rough tube provided by Haaland [31] was also plotted for comparison. It is
found that rough tube correlation has better prediction than that
of smooth tube correlation. Figures 10a and 10b show friction
factors of all test tubes as a function of Re. In laminar flow,
friction factors for all data sets approach the predictions from
conventional correlations in the low Re range. With increasing
(3)
Table 2 Uncertainties of the experimental apparatus and derived parameters
Apparatus
RTD
T-type thermocouple
Differential pressure transducers
Pressure transducer
Mass flowmeter
Laser confocal microscope
Derived parameters
Friction coefficient (f)
Nusselt number (Nud )
Reynolds number (Red )
Uncertainties
Calibration range
±0.1◦ C
±0.2◦ C
±0.075%
±0.4%
±0.6%
±0.1 μm
0–100◦ C
0–100◦ C
0–10 kPa
0–2 MPa
0–50 SLM
0–3 mm
0.8–9.6%
6.0–11.2%
0.3–32%
heat transfer engineering
Figure 8 Friction factor plotted as a function of Re for CO2 and air flow in
smooth tube. (Color figure available online.)
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T.-Y. LIN ET AL.
155
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Re, rough tubes (Tube B, Tube C, Tube D, and Tube E) show
friction factors higher than the predictions and the enhancement increases with Re. In turbulent flow, friction factors for all
rough tubes are significantly higher than the predictions from
the smooth tube correlation. The enhancement is higher than
that in the laminar flow. This is due to the thinner boundary
layer in turbulent flow, and the surface roughness seems to play
a more important role than that in the laminar flow. Besides
different surface configurations, two different fluids were tested
in the present study to investigate the fluid properties effects. As
can be seen from Figures 10a and 10b, there is no significant
difference between friction factor results for air and CO2 .
Heat Transfer Coefficient
Heat transfer coefficient h and Nu are calculated from the
following equation:
h=
q
,
(Tw,x − Tf,x )
and
Nu =
hdh
kf
(4)
where q is heat flux, Tw,x is internal wall temperature derived
from the external wall temperature measured by thermocouples,
and Tf,x is the local fluid temperature calculated from the energy
balance. Due to the low fluid heat capacity and small tube diameter in the present study, the heat losses, axial conduction,n and
viscous heating cannot be neglected. Detailed data reduction of
friction factor and heat transfer coefficient can be found in Lin
and Kandlikar [24] and Yang et al. [25].
Figure 11 shows the comparison of Nu for air and CO2 flow in
the smooth tube. Both air and CO2 data sets revealed that Nu can
be predicted well by the conventional correlations. In the laminar
flow with Re less than 2000, Nu remained constant, while in
turbulent flow with Re higher than 3000, Nu increases with
increasing of Re. The transition Re from laminar to turbulent
flow is the same as that for macroscale tubes. Figure 12 shows
Nu for air and CO2 in structured roughness Tube D at different
Figure 9 Comparison of friction factors by using hydraulic diameter and
constricted hydraulic diameter for Tube E. (Color figure available online.)
heat transfer engineering
Figure 10 Friction factors of all tubes in (a) air and (b) CO2 . (Color figure
available online.)
Figure 11 Heat transfer coefficient and Nu for air and CO2 flow in smooth
tube. (Color figure available online.)
vol. 35 no. 2 2014
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T.-Y. LIN ET AL.
Figure 12 Nu for Tube D as a function of Re for air and CO2 . (Color figure
available online.)
Figure 13 Nu for air and CO2 flow in all test tubes as a function of Re in
laminar flow. (Color figure available online.)
heating positions compared to the conventional correlations.
These data sets show a very small dependence on the heating
length. In laminar flow, Nu is slightly higher than the smooth
channel theoretical prediction. In turbulent flow, Nu is higher
than the smooth tube predictions for Re higher than 10,000.
However, there is no heat transfer enhancement observed for Re
in the range from 3,000 to 10,000. This is believed to be due to
the thinner boundary-layer thickness at high Re. The roughness
elements disturb the flow and cause flow mixing and enhance
heat transfer. In the lower Re region, the disturbance is relatively
weak and heat transfer enhancement is less. The boundary layer
thickness decreases with the increasing of Re in turbulent flow
and hence the enhancement is significant for high Re.
Figure 13 shows all Nu data for air and CO2 in all tubes
in laminar flow. The Nu approached the predicted value from
smooth tube correlations. In the higher Re region, the Nu is
slightly higher than for the conventional correlation. This is due
to the developing flow effects. In developing flow the boundarylayer thickness is thin and the heat transfer coefficient is high.
Developing length is a function of Re and increases with the
increasing of Re. Hence, in laminar flow Nu is slightly dependent
on Re and increases with increasing Re. The experimental results
concluded that there is no significant heat transfer enhancement
in the laminar flow due to roughness. There is no significant
difference among all the test tubes tested in laminar flow in the
present study.
Figure 14 shows Nu as function of Re for all tubes in turbulent flow. Unlike laminar flow, significant heat transfer enhancement due to roughness was observed. The heat transfer
enhancement order for the tubes from high to low is Tube B,
Tube C, Tube D, and Tube E. Nu for Tube B was observed
to be significantly higher than for the smooth channel correlation and the enhancement increases with increasing Re. This is
due to roughness elements disturbing the flow and causing flow
mixing, which results in enhanced heat transfer. Heat transfer
enhancement of Tube B is higher than Tube C due to the higher
roughness element height. Heat transfer enhancements for Tube
C and Tube D were observed only in the high Re region. The
uniform roughness tubes have a higher enhancement than the
structured roughness tubes due to turbulent eddies causing less
mixing on the tube grooves. Further study is needed to clarify
this phenomenon. In the lower Re turbulent flow region, Nu was
in good agreement with the conventional correlation. It should
be noted that the data sets in Figures 10a and 10b include both
air and CO2 data; hence it is concluded that there is no fluid
characteristics effect of the tubes in the present study both in the
laminar and in the turbulent flow.
CONCLUSIONS
Figure 14 Nu for air and CO2 flow in all test tubes as a function of Re in
turbulent flow. (Color figure available online.)
heat transfer engineering
Four internally roughened microtubes were successfully generated in the present study using electrodeposition of nickel on
sacrificial aluminum substrates. Friction factor and heat transfer
performance of air and CO2 flow in these tubes were studied.
vol. 35 no. 2 2014
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T.-Y. LIN ET AL.
The test results show that the friction factor and Nusselt number
in smooth tubes are in a very good agreement with those predicted by the conventional correlations in laminar and turbulent
flow regimes, whereas the friction factors in rough tubes are
significantly higher than the predicted values from the conventional correlations derived from macroscale rough tubes. The
use of constricted tube diameter proposed by Kandlikar et al.
[15] is recommended for uniform roughness and grooved tubes.
It may be noted that the internal diameters of nickel tubes used
in the friction factor and heat transfer calculations are the same
as the constricted tube diameters since the internal diameter
corresponds to the minimum flow diameter.
There is no heat transfer enhancement observed by the roughened surfaces in the laminar flow regime over the range of
parameters tested in this study. In turbulent flow regime, heat
transfer enhancement was observed and the enhancement ratio increases with increasing Reynolds number. In comparing
the heat transfer performance in various rough surface tubes,
the random roughened surface tubes (Tubes B and C) provided
higher heat transfer enhancement than the structured surface
tubes (Tubes D and E). Further studies are necessary to clarify
the effect of roughness element structures, geometries, and dimensions on the friction factor and heat transfer performance of
fluid flow in microtubes.
NOMENCLATURE
dcf
dh
di
f
H
h
kf
L
Nu
P
Pin
Pout
P
q
Re
Ra
Rc
T
Tf,x
Tw,x
constricted diameter, m
hydraulic diameter, m
internal diameter, m
Fanning friction factor, dimensionless
helical fin height, m
heat transfer coefficient, W/m2-◦ C
thermal conductivity of fluid, W/m-◦ C
length, m
Nusselt number, dimensionless
helical fin pitch, m
inlet pressure, Pa
outlet pressure, Pa
pressure drop, Pa
heat flux, W/m2
Reynolds number, dimensionless
average roughness, m
roughness, m
temperature, ◦ C
local fluid temperature, ◦ C
local wall temperature, ◦ C
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Ting-Yu (Tony) Lin received his Ph.D. in 2007 from
the Department of Mechanical Engineering at National Central University, Taiwan. He was a visiting
research assistant professor at Rochester Institute of
Technology, Rocjester, NY, from 2008 to 2011. He is
currently a thermal engineer in ZT Systems. His research interests include micro heat exchangers, heat
transfer enhancement, and microscale heat transfer.
He has published more than 20 journal and conference papers. Currently he is working on server and
switch cooling designs for data centers.
Chia-Wei Chen received his Ph.D. in 2011 from the
Department of Mechanical Engineering at National
Central University, Taiwan. His research interests
include air conditioning and fundamental research
in heat transfer characteristics in microchannels. He
also worked on heat transfer enhancement of spray
cooling on brazed aluminum heat exchangers. His
doctoral research focuses on heat transfer and friction characteristics of air and CO2 flow in rough and
smooth circular microtubes.
Chien-Yuh Yang is a professor in the Department of
Mechanical Engineering at the National Central University, Taiwan. He received his Ph.D. from Pennsylvania State University in 1994, and then joined the
National Central University in 1995. His current research interests include heat exchanger design, twophase heat transfer, heat transfer enhancement, and
microscale heat transfer. He has published more than
80 journal and conference papers and one textbook,
and has more than 10 heat exchanger-related patents.
Satish Kandlikar is the Gleason Professor of Mechanical Engineering at Rochester Institute of Technology (RIT), Rochester, NY. He received his Ph.D.
degree from the Indian Institute of Technology in
Bombay in 1975 and was a faculty member there
before coming to RIT in 1980. He has worked extensively in the area of flow boiling heat transfer and
CHF phenomena at microscale, single-phase flow in
microchannels, high heat flux chip cooling, and water management in PEM fuel cells. He has published
more than 200 journal and conference papers. He is a fellow of the ASME and
associate editor of a number of journals. He is the executive editor of Heat
Exchanger Design Handbook, published by Begell House. He received RIT’s
Eisenhart Outstanding Teaching Award in 1997 and RIT’s Trustees Outstanding
Scholarship Award in 2006. He received the 2008 Rochester Engineer of the
Year award from the Rochester Engineering Society. Currently he is working on
Department of Energy- and GM-sponsored projects on fuel cell water management under freezing conditions, and a National Science Foundation-sponsored
project on roughness effect on fluid flow and heat transfer at microscale.
vol. 35 no. 2 2014