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Proceedings of IMECE2006
2006 ASME International Mechanical Engineering Congress and Exposition
November 5-10, 2006, Chicago, Illinois, USA
Arun Muley‡, Joseph B. Borghese‡, Robert P Myott‡ , Carl Kiser* and Ramesh K. Shah†
Honeywell Aerospace, Torrance, CA 90504, USA
*Honeywell Transportation Systems, Torrance, CA 90505, USA
Subros Limited, C-51, Phase II, Noida 201304, UP, India
lightweight heat exchangers of this type, having advanced heat
transfer extended surfaces, have been developed for aerospace
applications where a premium is placed on size, weight, and
performance. These high performance heat exchanger designs
needs to adopted for high-volume, low-cost automotive type
manufacturing [1-3].
Thermal management (TM) for fuel cell and advanced
automotive applications plays a critical role in overall system
performance and is quite complex and challenging. Compact,
cost-effective, high performance and lightweight heat
exchangers are needed to meet high heat flux removal
requirements associated with these systems [1]. Innovative
heat transfer enhancement techniques such as, microchannel,
metallic foam and advanced platefin surfaces are being
considered for development of next generation of heat
exchangers that will meet these challenging demands [2-3].
These challenging demands are seen in radiators of fuel cell
powered passenger vehicles and for commercial transportation
applications. The upcoming 2010 off-highway emissions are
also driving the need for much improved performance in charge
air coolers and exhaust gas coolers [4]. The overall objective
of this study is to present the current state-of-the-art and
advances anticipated in the next generation heat exchanger
Several heat exchanger design concepts are being
developed to meet fuel cell system requirements. These include
state-of-art automotive type “tube-fin” and aerospace type
“plate-fin” radiator designs. A systematic performance
evaluation of different design concepts can be accomplished
using an equivalent system weight “Value Function (VF)”
approach. This more rigorous method aims towards better
understanding of the impact of different heat exchanger designs
on the TM systems. Preliminary results of this system level
radiator thermal performance evaluation indicate that the
standard automotive and aerospace designs are inadequate in
meeting overall system requirements. Cross-flow platefin
design that employs high aspect ratio, rectangular
microchannels on airside flow passages, offer substantial (up to
30-40%) weight/volume reduction over their standard
automotive and aerospace counterparts. An example of a
subscale microchannel heat exchanger is shown in Figure 1[3].
Research is being conducted to develop and characterize
thermal performance of these novel heat exchanger concepts as
efficient, cost-effective Balance of Plant (BOP) component of
fuel cell thermal management system.
For fuel cell automotive applications it is essential to
develop a low-cost, high performance thermal and water
management (TWM) system. Proton Exchange Membrane
(PEM) fuel cell offer high energy conversion efficiency, low
environmental and noise pollution and as such is suitable for
powering passenger cars. There is a need to develop an
integrated TWM system that efficiently uses the fuel cell waste
heat and water to minimize overall system weight and volume
without compromising overall system performance. Innovative
system architectures and novel component technologies are
being developed to meet challenges of increased performance,
compact design and low technical risks.
Waste heat generated by the PEM fuel cell cannot be easily
removed from the system because it is supplied with a
relatively low temperature. This requires heat exchangers with
high effectiveness to achieve compact systems. Compact,
Fig. 1. A view of liquid-air Microchannel Heat Exchanger [3]
Copyright © 2006 by ASME
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The 2010 global emissions legislations, shown in figure 2,
will have a major impact on heat exchanger design.
Fig. 4. Typical turbocharger compressor map with and without
EGR [4]
Fig. 2. Relative Timing of On-Highway and Off-Highway
Rules- A global Emission View [4]
Turbochargers are requiring much higher turbocharger
compressor discharge temperatures and mass flows. An
example of a typical turbocharger compressor map with and
without exhaust gas recirculation is shown in Figure 4. The
compressor discharge temperatures are as high as 575F and
challenge the viability of aluminum without a precooler. Also,
the potential corrosion is major concern as condensate at very
low pH numbers will occur over the wide range of engine
operating speed and load conditions.
These requirements are driving changes in engine
combustion systems, advanced air/fuel systems, exhaust after
treatment, vehicle drivelines, and electronics/control systems.
The engine and vehicle strategies for emission compliance are
providing many challenges in cooling components and systems.
There is going to be much higher temperatures, higher mass
flows, increased heat loads, and packaging issues in the 2010
time frame. Two NOx after treatment systems planned for this
time frame is the Low and High Pressure Loop Cooled Exhaust
Gas Recirculation Systems and are shown below in figure 3.
This presentation reports: (1) preliminary results from
thermal-hydraulic performance evaluation of microchannel and
metal foam heat exchangers (2) experimental pressure drop
measurements in prototype microchannel heat exchanger and
(3) preliminary results for metallic foam heat exchangers.
Finally, future development needs are summarized for their
successful insertion for full-scale production. The emissions
design impact on radiator, precoolers, charge air coolers, and
exhaust gas cooler design will be addressed in this presentation.
Each system will increase the vehicle/engine cooling heat
load by 25-30% as compared to current systems. The advanced
This study was supported in part by Honeywell Aerospace.
Also, the first author acknowledges support and encouragement
of Mr. Jorge Alvarez and Dr. Hal Strumpf.
1. R. K. Shah, “Heat Exchangers for Fuel Cell Systems,” in
Compact Heat Exchangers and Enhancement Technology
for the Process Industries-2003, pp. 205-215, R.K. Shah,
Editor, Begell House, New York, 2003.
2. Muley, A., Myott, B., Golecki, I., Borghese, J., Pohlman,
M., White, S. and Strumpf, H., “Advanced Thermal
Management Solutions for Aerospace Applications,”
presented in 2004 Sixth Biennial SAE Power Conference,
Reno, NV, 2004.
3. Muley, A., “Heat Transfer Enhancement for High
Performance Heat Exchanger,” presented in 2006 Post
ISMHT-ASME Workshop on Compact Heat Exchangers,
IIT Madras, Chennai, India, 2006.
4. Kiser, Carl, “Honeywell Turbo Technologies (Thermal
Systems)”, presented at Tokyo Motor Show Symposium,
Tokyo, Japan, 2004.
Fig. 3. NOx after treatment Systems: (a) High Pressure
and (b) Low Pressure Exhaust gas Recirculation [4]
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