Thermal management with double layered heat sink produced by direct metal laser sintering

Abstract

In this study, the thermal management of a heat sink which is the heart of a cold plate is investigated considering Additive Manufacturing (AM) technology. Although AM enables many flexibilities, it also brings some limits to design and manufacturing. In general, a cold plate is developed to cool many heat sources with an appropriate heat sink design just under the sources to have a maximum cooling rate. Due to the nature of Direct Metal Laser Sintering (DMLS) AM technology, we have to use some supports (used as pin fins in this study) to avoid material collapse to have a rugged and fine product. In this study, straight rectangular channels with the production limit of AM technologies have been investigated in detail and the results are compared to investigate the heat treatment effect for the same design. Due to its cooling advantages in a confined space, a double-layered heat sink is chosen as the heat sink geometry to reach the goals. In order to succeed in electronic performance requirements, two heat sources on each side of the plate (heat sink) must be so cooled that their temperatures are close to each other. This is one of the requirements in radar electronics to have higher performance and to decrease the necessary calibration efforts. Deliberately, the heat load is selected as 100W/cm2 using mini or smaller channel sizes to enforce the limits of AM technology. One of the most important aspects of a cold plate design is to distribute the fluid to the heat sources to collect it properly without sacrificing electronic components and use the space effectively. As a result; The Double Layered Heat Sink design allows temperature difference between the heat sources to be kept around 1°C with 100W/cm2 heat flux.