Closed Loop Liquid Cooling of High Powered CPUs

Abstract

This case study presents an experimental investigation of closed loop liquid cooling of CPUs. The cooling system implements a pumped liquid supplying a cold plate fixed to the emulated CPU heat source and a remote Air-Cooled Heat Exchanger (ACHE). The Hybrid Liquid-Air (HLA) system employs 25% v/v Arteco-Freecor with distilled water solution as the primary coolant, and air as the secondary coolant. The thermal-hydraulic performance of the system is characterized over a range of operating conditions, including CPU heat loads (12 W/cm2 – 72 W/cm2), water volumetric flow rates (0.5 L/min – 8 L/min), and air velocities (1m/s – 3m/s). In order to provide a performance frame of reference, evaluations were also conducted with a conventional air-based fan- fin CPU cooling system.