Prediction of flow boiling characteristics in manifold microchannel radiator based on high heat flux cooling

Manifold microchannel (MMC) heat sinks are a hot research topic in the field of electronics cooling due to their excellent performance in handling high heat flux. Significant progress has been made in recent years in the study of MMC boiling and heat dissipation characteristics, but the use of numerical simulation remains an important tool for predicting the flow boiling characteristics of MMC heat sinks at high heat fluxes because of the difficulty in observing and the short phase transition times in MMC microchannel boiling experiments. In this study, transient flow boiling in manifold microchannels is numerically simulated based on the Volume of Fluid (VOF) phase transition model. The effects of the MMC inlet-to-outlet width ratio ($\alpha$), microchannel height-to-width ratio ($\beta$), and microchannel width-to-total width ratio ($\gamma$) on the flow boiling characteristics are systematically investigated from the perspective of bubble dynamics behavior. A manifold microchannel radiator flow boiling prediction model is developed by designing a mixed factor experiment using Taguchi’s method with a comprehensive evaluation factor as the prediction target. Under the working condition parameters set in this study, when the inlet-to-outlet width ratio ($\alpha$) is 1, the microchannel height-to-width ratio ($\beta$) is 0.24, and the microchannel width-to-total width ratio ($\gamma$) is 0.7, a manifold microchannel integrated evaluation factor of 83.51 is obtained, and this prediction is in high agreement with the experimental data. In addition, applying the prediction model of this study to the experimental data of MMC radiators by previous researchers, the error range is controlled within 9%, which further confirms the validity and reliability of the present model. The findings of this study serve as a valuable reference point for the subsequent design and optimization of manifold microchannel boiling radiators.