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High temperatures can cause the performance of the microprocessor
to be low. Hence the generated heat must be removed or dissipated.
Many common devices are used to accomplish this function. Heat
pipes, described in the following discussion, are commonly used,
for example, to transfer heat from a microprocessor to some type
of heat sink or dissipater in a unit. In this particular example, the
needed capacity of the heat pipe to transfer heat could be fairly easily
determined from the specifications of the microprocessor. Improvements in heat transfer that are possible via the uses of nanofluids
and highly conductive nanomaterial composites (see the following
discussion) would enable the heat pipe to be made smaller and/or
to conduct heat away more quickly.
The aim of many other devices is to directly provide a heating
or cooling source or environment. A common refrigerator, for
example, is intended to provide a controlled cooling environment.
The intended use provides specifications for how much heat is to
be removed or what kind of temperature environment is to be provided. Design questions then hinge around what is the best set of
devices and material constructions for accomplishing these ends.
Invariably the desire is to have the present basic energy conversion
device be highly efficient (and thus use as little external energy as
possible) and be as small as possible. For many products, added
design issues include quietness of operations, lack of vibration,
and so forth. Improved solid-state components that are inherently
quiet, such as thermoelectric devices (see the following discussion),
and that are based on nanotechnologies promise to meet some of
these design needs.
Designing these kinds of thermal management systems in most
devices normally hinges around selecting materials and developing
related components that in some way either maximize or minimize
heat transfer via conduction, radiation, or convection, depending
on the design circumstance. For materials used directly, common
property measures such as thermal conductivity can be used directly.
Many devices that might accomplish some overall heat management function, however, are quite complex and might simultaneously involve several mechanisms. The heat pipes noted previously,
for example, appear simple and have a clear overall function of
transferring heat from one point to another but involve the use of
not only thermoconductive materials but an internal fluid in both
liquid and vapor phases. These and other more complex forms of
devices are discussed more extensively in the following sections.
Certainly the potential of various nanomaterials to optimize material properties is great.
The Thermal Environment
High temperatures can cause the performance of the microprocessor
to be low. Hence the generated heat must be removed or dissipated.
Many common devices are used to accomplish this function. Heat
pipes, described in the following discussion, are commonly used,
for example, to transfer heat from a microprocessor to some type
of heat sink or dissipater in a unit. In this particular example, the
needed capacity of the heat pipe to transfer heat could be fairly easily
determined from the specifications of the microprocessor. Improvements in heat transfer that are possible via the uses of nanofluids
and highly conductive nanomaterial composites (see the following
discussion) would enable the heat pipe to be made smaller and/or
to conduct heat away more quickly.
The aim of many other devices is to directly provide a heating
or cooling source or environment. A common refrigerator, for
example, is intended to provide a controlled cooling environment.
The intended use provides specifications for how much heat is to
be removed or what kind of temperature environment is to be provided. Design questions then hinge around what is the best set of
devices and material constructions for accomplishing these ends.
Invariably the desire is to have the present basic energy conversion
device be highly efficient (and thus use as little external energy as
possible) and be as small as possible. For many products, added
design issues include quietness of operations, lack of vibration,
and so forth. Improved solid-state components that are inherently
quiet, such as thermoelectric devices (see the following discussion),
and that are based on nanotechnologies promise to meet some of
these design needs.
Designing these kinds of thermal management systems in most
devices normally hinges around selecting materials and developing
related components that in some way either maximize or minimize
heat transfer via conduction, radiation, or convection, depending
on the design circumstance. For materials used directly, common
property measures such as thermal conductivity can be used directly.
Many devices that might accomplish some overall heat management function, however, are quite complex and might simultaneously involve several mechanisms. The heat pipes noted previously,
for example, appear simple and have a clear overall function of
transferring heat from one point to another but involve the use of
not only thermoconductive materials but an internal fluid in both
liquid and vapor phases. These and other more complex forms of
devices are discussed more extensively in the following sections.
Certainly the potential of various nanomaterials to optimize material properties is great.
The Thermal Environment