NEPCM in High-Flux Electronics and Chip-Level Cooling
Problem Space:
Investigate the integration of NEPCM and microchannels for cooling microelectronic devices
Abstract:
The growing demand for microelectronic systems to be
smaller and faster has increased the energy released by these
devices in the form of heat. Microelectronic systems such as
laptop computers and hand held devices are not exempted from
these demands. The primary traditional technologies currently
used to remove heat generated in these devices are fins and
fans. In this study, traditional methods were compared to more
novel methods like cooling using forced convection in
microfluidic channels and stagnant nanoparticle enhanced
phase change materials (NEPCM). For this study, the difference
between the surface temperature of a simulated microelectronic
system without any cooling and with a particular cooling
method was compared for several cooling scenarios. Higher ΔT
values indicate more effective cooling. The average ΔT values
for fans, fins, NEPCM and microchannels with water were 2°C,
5°C, 3°C and 4°C respectively. These results suggest that,
separately, microchannel cooling and NEPCM are promising
methods for managing heat in microelectronic systems.
Even more interesting than NEPCM or microchannel
cooling alone is the potential cooling that can be achieved by
combining the two methods to achieve multimode cooling first
by the phase change of the NEPCM and then by circulating the
nanofluid (melted NEPCM) through microchannels. A
feasibility assessment, however, reveals that the combination of
the two methods is not equal to the sum of the parts due to the
viscosity and associated pumping power requirements for the
melted phase change material. Nonetheless, the combination of
the method still holds promise as a competitive alternative to
existing thermal management solutions.
Relevant Data:
Abstract:
The growing demand for microelectronic systems to be smaller and faster has increased the energy released by these devices in the form of heat. Microelectronic systems such as laptop computers and hand held devices are not exempted from these demands. The primary traditional technologies currently used to remove heat generated in these devices are fins and fans. In this study, traditional methods were compared to more novel methods like cooling using forced convection in microfluidic channels and stagnant nanostructure enhanced phase change materials (NEPCM).
The first objective for this study was to develop a testing station to simulate the heating observed for microelectronic devices. This station consisted of an aluminum bar with a cartridge heater inserted. A power transformer provided power to the cartridge heater, which heated the aluminum bar to simulate a heated microelectronic device. Surface mounting thermocouples measured the temperature of the aluminum bar and either a multimeter, multi-thermocouple controller or automated data acquisition system reported the temperatures measured by the thermocouples. Additonally, the station was characterized using a lumped parameter analytical model. The experiments and model were in good agreement.
After developing the test station, traditional cooling methods were studied. A fan powered by a 10 V power supply and an aluminum fin array with a total surface area of approximately 0.1 square meters were investigated. For these studies, the difference between the surface temperature of a simulated microelectronic system without any cooling and with a particular cooling method was compared for several cooling scenarios. Higher ΔT values indicate more effective cooling. The average ΔT values for the fans and fins studies were 2°C and 5°C, respectively.
Next, novel cooling methods were investigated. The first novel cooling method investigated was NEPCM. The NEPCMs for this study were eicosane, a paraffin, infused with either copper oxide nanoparticles or carbon nanotubes to enhance the thermal conductivity. The second novel method investigated was microchannels with water as the cooling fluid. Results obtained from these studies indicated 4°C of cooling for both methods. These results suggest that, separately, microchannel cooling and NEPCM are promising methods for managing heat in microelectronic systems.
Relevant Data: