Numerical analysis of flow and heat transfer characteristics of double-layer heterogeneous single crystal diamond microchannel heat sinks

In order to solve the heat dissipation problems associated with highly integrated and high heat flux microelectronic devices, in this work, a novel type double-layer heterogeneous single crystal diamond microchannel heat sink (DLH-SCD-MCHS) is designed and numerically analyzed, in which the upper channel is rectangular and the lower channel consists of various cavities and rib combinations. The comprehensive performance of the DLH-SCD-MCHS was analyzed by the correlation with pumping power and thermal resistance, and the enhanced heat transfer factor (η). The outcome shows that the DLH-SCD-MCHS significantly enhances the heat transfer while appropriately sacrificing part of the pressure drop. Compared with the traditional double-layer microchannel heat sink (DL-MCHS), the pressure drop of DLH-SCD-MCHS is increased by 23.8–43.5 %, the heat transfer coefficient is enhanced by 74.5–117.1 %, and the η is improved by 62.5–87.4 %. The DLH-SCD-MCHS can reduce the irreversible loss, and the minimum augmentation entropy generation number is 0.64 for the DLH-SCD-MCHS with rectangular cavity and rectangular rib (Model V). As Re = 874, the relative rib width, the relative rib length and the relative position of the ribs of the Model V are 0.5, 0.571 and 0.5, respectively, the maximum η is 1.97. The DLH-SCD-MCHS provides new insights for the management of the heat transfer system of microelectronic devices.