PRODUCTS & SERVICES
Cool runnings
Using a combination of simulation tools innovative manufacturing methods
and rig testingcan maximize the performance of cold plate devices
Example of a liquid cold plate designed and manufactured by PWR Advanced Cooling Technology
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A cold plate is a generic name
for a device used to provide
cooling of electronic components or
energy storage systems. The heat
dissipating devices are cooled
through direct contact with the
surface of the cold plate. The
generated heat can be extracted by
ensuring a su icient temperature
di erence between the electronic
components and the cooling
medium within the cold plate. Heat
is transferred to the cold plate first
by conduction and is then carried
away by convection.
The choice of the conductive
material and the fluid to transport
the heat are paramount in the
design of a cold plate, to ensure
e icient heat transport. In addition,
cold plates o er the advantage of
providing a sealed environment so
that the fluid employed for heat
transport does not come in contact
with any electronic connections.
This gives the opportunity to use
higher heat capacity fluids and
create more e icient cold plates.
The primary material choice for
cold plates remains aluminium due
to its high thermal conductivity and
low specific weight compared to
other metals. This does come
however at a price. Specific
production processes are required
to keep surface finish and planarity,
due to the large thermal expansion
of the material, without which the
end-product would o er a less than
ideal thermal contact between the
cold plate and the electronic device,
reducing the energy storage
system’s e iciency.
The cold plate can be used with
a wide variety of coolant types from
water and glycol mixes, through to
the vast array of the dielectric fluids
available on the market. Depending
on the choice of fluid and packaging
constraints, PWR is able to
implement a solution tailored to the
client’s specification, while being
able to prove the initial concept on
a specific, purpose-built test rig.
The test rig is setup to simulate
the heat input from the electronic
components which are required to
be cooled. Using the
aforementioned fluids, a consistent
mapping of the heat transfer
coe icients and pressure drops for
di erent flow rates can be extracted.
Normalizing the extracted data
requires additional post processing
but has several benefits. First of all,
to ensure quality of the recorded
measurements, as outliers can be
easily detected. Secondly, the
normalized data is used for
prediction tools capable of sizing
the final cold plate prototypes that
will match cooling requirements.
Lastly, the data is used to identify
the flow regimes for the internal
fluid, which will enable specific
designs to extract heat e iciently
based on the internal heat exchange
surface and geometry.
PWR continuously develops the
methodology and simulation tools
to enable it to predict the
performance of cold plates or any
types of radiators and heat
exchangers, which PWR produces.
To this end, extracting relevant
information such as pressure drop
and heat transfer coe icients using
its on-site testing facility allows it to
deliver better consistency between
test results and simulation data. In
turn, the output from prediction
tools can be used to drive the
development of more e icient cold
plate designs.
A test rig setup showing the cold plate between two heater blocks
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