Thermal characteristics of a flat plate pulsating heat pipe module for onsite cooling of high power server CPUs

Abstract

• An aluminum flat plate pulsating heat pipe radiator was developed for server chip cooling. • The optimal filling rate is about 75-80% with the minimum total thermal resistance of 0.225℃/W. • The cooling module can solve 250W heat load with the chip temperature below 85℃. • The cooling module is more superior in thermal performance to the commercial vapor chamber module. In order to meet the increasing power density and heat dissipation requirements of data center servers, an aluminum-based flat plate pulsating heat pipe module characterized with locally heated on the central region and cooled on the entire rest sides was proposed. Using acetone and R113 as the working fluids, the heat dissipation performance under different liquid filling rates was experimentally studied. Under the condition of the optimal filling rate (75-80%), the heat dissipation capability of 250W can be achieved for acetone with the minimum thermal resistance of 0.225℃/W. Meanwhile, this aluminum-based flat plate pulsating heat pipe module was compared with those of the large FPPHPs and vapor chambers reported in other literatures, especially with the currently available commercial vapor chambers in terms of total thermal resistance and thermal diffusivity, indicating the flat plate pulsating heat pipe module proposed herein is more superior in thermal performance. The flat plate pulsating heat pipe module owns advantages of low cost, light weight and robustness compared to other commercial high power server solutions.