|Description:|| ASTRON/JIVE have taken the firs steps towards liquid cooling of UniBoards. In the image, the setup is shown. For this first step, the heat sinks of two FPGAs are replaced by water blocks. A special liquid is pumped trough the water block to remove the heat from the FPGAs. The heated liquid is then cooled down in the radiator (left in the image). The FPGA temperatures are read by the laptop. |
Even when the system running at half speed (fans in the radiator at half speed and water flow at half speed) the selected FPGAs are cooler (41°C instead of 57°C) than the other ones.
The goal of liquid cooling is to increase the efficiency. Normally, forced-air cooling is used, where an airflow passes the FPGAs. This heated air is removed from the subrack into to cabinet, and another set of fans or an airco is used to remove the heat from the cabinet.
With liquid cooling, the heat exchange can be done from the FPGA to the outside of the cabinet, thus reducing the number of fans, or the capacity of the airco. Above all, we expect a higher cooling capacity with liquid cooling, which will be needed for future FPGA boards.
The next step will be to cool all eight FPGAs on a UniBoard. This technology will then be used for UniBoard2.