5
The need to meet accelerated 2002 EPA standards for NO
x
reduction [3] has focused
attention on the truck thermal-management system. This is because near-term emissions-control
strategy involves EGR, and the need to provide EGR cooling can be expected to add 20 to 50%
to the coolant heat rejection requirements. The large-truck industry's desire to go to higher-
horsepower engines only exacerbates an already difficult situation. It has been an industry goal to
keep the heat exchanger package from growing due to increased heat rejection demands.
However, with the additional heat load of EGR cooling, this will be an unavoidable challenge.
Keeping the heat exchanger package from growing can realistically be accomplished only by
developing new technologies, e.g., innovative techniques to improve airside heat transfer, and/or
new thermal management concepts. New concepts, on the other hand, can be expected to lead to
an increase in system complexity, with a concurrent increase in cost for components, production,
and service.
strategy involves EGR, and the need to provide EGR cooling can be expected to add 20 to 50%
to the coolant heat rejection requirements. The large-truck industry's desire to go to higher-
horsepower engines only exacerbates an already difficult situation. It has been an industry goal to
keep the heat exchanger package from growing due to increased heat rejection demands.
However, with the additional heat load of EGR cooling, this will be an unavoidable challenge.
Keeping the heat exchanger package from growing can realistically be accomplished only by
developing new technologies, e.g., innovative techniques to improve airside heat transfer, and/or
new thermal management concepts. New concepts, on the other hand, can be expected to lead to
an increase in system complexity, with a concurrent increase in cost for components, production,
and service.
Thermal management is a systems technology with far-reaching effects. The trucking
industry and its component suppliers are well aware of the broad implications of thermal
management and continue to improve component and system designs. Nevertheless, there is a
need for new and innovative technologies and concepts whose development is appropriate for
government funding. While improved fuel economy is of interest to fleet operators, it is not their
top priority, especially if it is achieved at the expense of higher capital cost for the truck.
Similarly, emissions reduction becomes a high-priority item only when government regulations
require it. On the other hand, fuel economy and emissions reduction are both high-priority
objectives of the DOE.
management and continue to improve component and system designs. Nevertheless, there is a
need for new and innovative technologies and concepts whose development is appropriate for
government funding. While improved fuel economy is of interest to fleet operators, it is not their
top priority, especially if it is achieved at the expense of higher capital cost for the truck.
Similarly, emissions reduction becomes a high-priority item only when government regulations
require it. On the other hand, fuel economy and emissions reduction are both high-priority
objectives of the DOE.
The consensus of the trucking industry (both end-users and equipment suppliers) is that
the time is right for assessing the state of the art in thermal management for large trucks and for
the development and application of new and innovative technologies and advanced thermal-
management-system concepts. Successful implementation of any new concept will require
research and component development, together with close cooperation among equipment
suppliers, engine manufacturers, truck manufacturers, and researchers. Barriers to the application
of new technology include cost (both initial and life-cycle), complexity, and industry demand for
high reliability and durability, and these account for much of the conservatism in the design of
thermal management components. These barriers must be addressed and overcome.
the development and application of new and innovative technologies and advanced thermal-
management-system concepts. Successful implementation of any new concept will require
research and component development, together with close cooperation among equipment
suppliers, engine manufacturers, truck manufacturers, and researchers. Barriers to the application
of new technology include cost (both initial and life-cycle), complexity, and industry demand for
high reliability and durability, and these account for much of the conservatism in the design of
thermal management components. These barriers must be addressed and overcome.
A workshop on Thermal Management for Heavy Vehicles, with the objective to obtain
industry input to the development of DOE/OHVT's multiyear program plan for thermal
management in heavy vehicles, specifically Class 7-8 trucks, was sponsored by DOE/OHVT and
held at Argonne National Laboratory on October 19-20, 1999. The workshop objective was
accomplished by creating a forum for engine manufacturers, truck manufacturers, fleet operators,
equipment suppliers, the DOE, national laboratories, universities, and research organizations, to
management in heavy vehicles, specifically Class 7-8 trucks, was sponsored by DOE/OHVT and
held at Argonne National Laboratory on October 19-20, 1999. The workshop objective was
accomplished by creating a forum for engine manufacturers, truck manufacturers, fleet operators,
equipment suppliers, the DOE, national laboratories, universities, and research organizations, to
·
Review performance objectives and future trends in the large-truck industry
and their influence on thermal management.
and their influence on thermal management.