Research on cooling high-power multi-core processors: Based on a hybrid microchannel multiple array pin fin heat sink

With the increasing power density of modern processors, effective management of hotspot temperatures has become a critical challenge in thermal design. This study proposes a novel hybrid microchannel heat sink incorporating multiple arrays of cylindrical pin fins for efficient thermal regulation in multi-core processors operating under high heat flux. The proposed design utilizes rectangular microchannels in regions of low heat flux (common zones) and integrates cylindrical pin fin arrays in high heat flux regions (hotspots) to enhance localized cooling performance. The thermal performance of this hybrid structure is evaluated numerically based on key metrics, including thermal resistance (Rtot), pressure drop (?pmax,ch and ?pavg,ch), pumping power (Ptot), temperature non-uniformity (?Ths and ?Tbot), maximum temperature at hotspot (Tmax,hs), and entropy production (S). Additionally, to examine the influence of thermophysical properties of refrigerants on heat sink performance, the study simulates and compares the phase change cooling characteristics of several commonly used organic refrigerants. Compared to the hybrid microchannel heat sink with a single pin fin array, the multiple array structure achieves similar pressure drop and pumping power, while reducing thermal resistance and S by 4% and 7%, respectively. In contrast, ?Ths and ?Tbot are reduced by approximately 30% to 50%.